Monthly Precipitation Summary

State of Hawaii

Month: February 2026

Prepared: March 5, 2026

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

Headline: Very wet month for windward areas statewide with two main heavy rain/flooding events; leeward areas predominantly left out of the action.

February began under a weak subtropical ridge, producing light winds and stable conditions with limited cloud and shower development statewide. Strong and gusty southwest winds developed on the 2nd ahead of a fast-moving cold front, producing localized downslope wind gusts and scattered power outages in areas north and east of the mountains. The front moved quickly down the island chain overnight, bringing a brief period of locally heavy showers with totals generally one-half inch or less, locally up to one inch on Oʻahu. Cooler, drier air and decreasing winds followed as the front dissipated near the Big Island. Dry weather and light winds persisted through the 5th.

Another approaching front shifted winds out of the south on the 6th and brought enhanced pre-frontal showers to portions of the smaller islands. The front moved through the western islands on the 7th and stalled near Maui through the 10th. Abundant moisture pooled along the boundary and, combined with instability from an upper-level disturbance, produced a prolonged period of heavy rainfall. Persistent north to northeast winds focused rainfall along windward and upslope areas, where three-day totals (ending at midnight HST on the 10th) commonly exceeded 4 inches. Swaths of 8 to 12+ inches occurred across windward portions of the Big Island, Maui, Molokaʻi, and Oʻahu, with localized totals near 25 to 30 inches. Most of the rain fell on the 8th and 9th. Despite the large totals, rainfall rates were generally modest—around 1 to 2 inches per hour—limiting flash flooding impacts. Saturated soils did contribute to landslides near Waipiʻo Valley and Laupāhoehoe. Strong northeast winds behind the front also produced scattered power outages and downed trees in wind-prone valleys and leeward mountain areas.

Breezy to locally windy trade winds prevailed from the 11th through the 19th with periodic windward and mauka showers. The wettest period occurred from the 14th through the 16th, when north and east slopes of Maui and the Big Island received roughly 0.75 to 1.5 inches of rain per day, with isolated higher amounts in favored terrain. Oʻahu and Kauaʻi received lighter totals, mainly on the 15th.

A vigorous upper-level trough approached the island chain on the 20th, producing periods of heavy rain from Kauaʻi to Maui that evening with rainfall rates generally between one-half and one inch per hour. Rising water levels along the Hanalei River briefly flooded portions of Kūhiō Highway near the bridge in Hanalei after midnight on the 21st, forcing a temporary closure.

As the trough moved closer to the state later on the 21st, increasing instability and very cold temperatures aloft combined with strong orographic lift along the Koʻolau Mountains of Oʻahu to produce an intense, nearly stationary band of heavy rain and thunderstorms along the upper windward slopes and ridgeline of the mountain range. The heaviest rainfall occurred between Maunawili and Hauʻula during the mid-morning and persisted for several hours. Rainfall rates commonly reached 2 to 4 inches per hour in that area, with brief peaks exceeding 6 inches per hour. Some notable rainfall rates across Oʻahu include: Luluku with 17.07 inches in 6 hours (13.01 inches in 3 hours), USGS Moanalua RG with 13.44 inches in 6 hours (12.49 inches in 3 hours), and USGS Poamoho RG1 with 13.09 inches in 6 hours (8.10 inches in 3 hours). For some perspective, these 6-hour rainfall rates have a less than 1% chance of occurring in any given year. Those three sites also had the top three 24-hour totals for the entire state on the 21st (Luluku - 25.10 inches, Moanalua RG - 17.51 inches, and Poamoho RG1 - 16.32 inches). These extreme rainfall rates produced rapid stream rises and overwhelmed drainage systems.

Significant flash flooding occurred along windward Oʻahu, particularly around Kāneʻohe, Waiāhole, and Waikāne, where overflowing streams flooded roads, homes, and vehicles. Several roads closed, including the Likelike Highway off-ramp from the Kāneʻohe-bound H-3 Freeway. Floodwaters also affected parts of the North Shore near Waialua and Haleʻiwa after runoff from the Koʻolau Mountains filled Wahiawā Reservoir and overflowed its spillway, flooding nearby agricultural areas and portions of the Otake Camp community. Most homes there avoided major damage due to elevated construction.

Windward Molokaʻi and Maui also received heavy rainfall during the event, though totals were lower than on Oʻahu. These areas generally recorded 2 to 7 inches, with the highest totals near Hāna on Maui and in the Hālawa area of Molokaʻi. Landslides were reported along the Hāna Highway, temporarily closing the road while crews removed debris.

The upper trough lingered through the 23rd. Increasing trade winds interacting with lingering instability produced additional moderate to heavy showers over windward slopes of Maui County and the Big Island, where totals were in the neighborhood of 1 to 3 inches. Cooler, drier trade winds returned from the 24th through the 26th. Winds gradually weakened and shifted east-southeasterly during the final days of the month, allowing temperatures to warm slightly while shower activity decreased.

Island of Kauaʻi : [February 2026 map] [year-to-date map]

Interior and windward portions of the island came in well above average for February, with several windward upslope spots receiving more than double their usual February amounts. Leeward (southwest and west) areas were all below average, mainly in the 40 to 70% below average range. The USGS gage on Mt. Waiʻaleʻale had the highest monthly total for the island and the state for the 2nd month in a row with 52.71 inches (216% of average), as well as the highest daily total for the island with 7.09 inches on the 9th.

The year to date (YTD) totals and percentages of average were distributed largely the same as the February numbers, with windward and interior above average and the remainder of the island below average. The highest YTD total belongs to Mt. Waiʻaleʻale with 79.93 inches (162% of average).

Island of Oʻahu: [February 2026 map] [year-to-date map]

What a difference a month can make! Nearly every site on Oʻahu was above average this month, with the majority of those around 2 to 4 times their February averages; a great rebound from a below average January. The highest totals occurred over and along the upper windward slopes of the Koʻolau Mountains, mostly due to the heavy rain event on the 21st. The highest total for the month came from the USGS Moanalua RG site with 41.87 inches, (an incredible 451% of average). The top daily total for Oʻahu (and the state as a whole) came from the NWS Luluku gage with 25.10 inches on the 21st. This site also set a record for its wettest February (period of record since 1916). The NWS Palisades site also set a record for their wettest February (since 1991). Several other sites recorded their wettest February as well: Ahuimanu Loop (since 1991 –caveat: missing data for February in 2000 and 2001, but relatively dry Februarys at the nearby Waihee Pump gage during those two years), Kamananui RG (since 2013), Moanalua RG (since 2011 – beat previous record by over 20 inches), Poamoho RG1 (since 2013), Pūpūkea RG (since 2013), and Tunnel RG (since 2013).

The year to date (YTD) totals and percentages of average were largely well above normal as well, with the exception of some leeward locations in the 60 to 90% range below average. The highest YTD total was the USGS Tunnel RG with 50.66 inches (241% of average), which only narrowly edged out the Moanalua RG (50.61 inches, 232% of average).

Maui County: [Maui February 2026 map] [year-to-date map] [Molokaʻi/Lanaʻi February 2026 map] [year-to-date map]

Maui County also fared much better in February, all but a handful of sites coming in near to well above average for the month. Due to the dominant weather patterns in February, the highest amounts were generally focused along the windward mountain slopes of each island with most sites around 2 to 3 times their February averages. Leeward areas were generally below average (40 to 80%). Interestingly, enough rain fell in the Maui central valley to give sites like Wailuku, Kahului Airport, and Kealia Pond around 150 to 200% of their monthly average rainfall, which bodes very well for drought conditions there. Note: several sites on Maui are still missing for the month due to maintenance issues, but are expected to be available for use in the March rainfall summary. The USGS W. Wailuaiki Stream site on Maui held the top spot for monthly total in the county with 46.12 inches (311% of average). The highest daily total, however, went to Puʻu Kukui with 10.48 inches on the 8th. This site also had the second highest daily total for the county with 9.67 inches on the 9th. The W. Wailuaiki Stream site on Maui had its wettest February since 2016, while Puʻu Aliʻi on Molokaʻi had its second wettest February since 2015.

The year to date (YTD) totals and percentages of average were distributed largely the same as February, with windward and central areas near to above average and leeward below average. The highest YTD total was at W. Wailuaiki Stream with 62.10 inches (178% of average).

Island of Hawaiʻi: [February 2026 map] [year-to-date map]

The North Kohala, Hāmākua, Hilo, and Puna Districts raked in the rainfall in February due to the event over the first weekend of the month. All of the gages in these areas came in above average for the month, some 2 to 3 times their averages. Even most of leeward North Kohala got enough rainfall to come in just above average for February, likely due to the strong trade winds pushing showers over the mountains in that area. The NWS site at Honokaʻa recorded its wettest February on record (since 1991 – caveat: missing data for February in 2011 and 2019, though nearby data sites had nowhere near 30 inches during those two years). Kahua Ranch also had its wettest February on record (since 1993). The Kawainui Stream site had its wettest February since 2010. The remaining areas of the island (interior and leeward) were well below average for the month, mostly 40 to 80% of average, with the exception of a few upslope sites in the Kona District coming in just above average. The highest monthly total for February came from the USGS Kawainui Stream rain gage with 36.91 inches (385% of average). The highest daily total for the island came from the NWS Honokaʻa site with 9.99 inches on the 8th.

The year to date (YTD) totals and percentages of average were well above average for windward portions of the island and still generally below average for leeward and interior areas. The highest YTD total goes to the USGS Honoliʻi Stream site with 52.37 inches (167% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey (USGS), the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: January 2026

Prepared: February 5, 2026

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

Headline: Eastern/southern Big Island finally gets some much-needed rain. Mainly windward and mauka rain elsewhere across the state.

January opened with moderate trades and enhanced windward showers from a dissipating front. The most notable rainfall occurred on the Big Island, where Hilo Airport set a new daily rainfall record on the 3rd with 3.24 inches.

A kona low developed north-northwest of Kauaʻi on the 4th, shifting winds out of the south and pulling deep tropical moisture into the state. Showers and thunderstorms first focused over Kauaʻi and Oʻahu, before shifting to the southeast slopes of the Big Island as winds shifted out of the southeast. Southeast Big Island between Hilo and South Point received the heaviest rainfall, with widespread totals (mainly on the 4th and 5th) of 4 to 10 inches and a broad area of 8 to just over 14 inches from Mountain View to Nā‘ālehu, including parts of Hawaiʻi Volcanoes National Park. Kauaʻi and Oʻahu generally received 3-day totals of 1 to 3 inches, with isolated totals near 5 inches on central Kauaʻi. Overall, flood impacts were minor, though flood waters did close a section of Māmalahoa Highway near Kawa Flats near the southern end of the Big Island.

Conditions became drier and more stable from the 8th through the 11th. Two fast-moving fronts crossed the state around mid-month, bringing modest rainfall on the 12th and a wetter event on the 14th and 15th with totals around 1 to 3 inches on Kauaʻi, 1 to 1.5 inches on Oʻahu and Maui County, and up to 1 inch on the Big Island. Cooler and drier northerly winds filled in behind the front, with breezy trades developing and continued dry weather dominating through the 19th.

Another front moved down the island chain from the 20th to the 22nd and stalled near Maui County, with most rain falling on the 21st along north- and east-facing slopes (generally 1 to 1.5 inches, locally near 3 inches) of most islands. Several Flood Advisories were issued for the heavy rain. Two hikers were rescued by helicopter near mile marker 5 of the Hāna Highway due to rising stream levels cutting them off from the rest of their group. Additional heavy showers fell over windward Maui on the 23rd before the front dissipated.

Light southeast to southerly winds and scattered showers followed on the 24th and 25th ahead of a weakening front, which briefly increased showers over Kauaʻi and Oʻahu into the 26th. Dry conditions returned from the 27th to the 29th. A weak front rounded out the month, with light to moderate showers mainly along north and east facing slopes, with amounts around 0.5 to 1 inch.

Island of Kauaʻi: [January 2026 map]

The first month of the year was a mixed bag for Kauaʻi (and most of the rest of the islands). The rain events in January tended to be a bit spottier and north/east slope-focused than the widespread large amounts of December. Generally speaking, inland sites and those along the northern coast came in near to above average for the month, while most other areas of the island were around 50 to 80% of their January averages. A few spots, mainly along the southern coast, were closer to 30 to 40% of average. The USGS gage on Mt. Waiʻaleʻale had the highest monthly total for the island and the state with 27.22 inches (110% of average), as well as the highest daily total for the island with 8.76 inches on the 6th.

Island of Oʻahu: [January 2026 map]

The majority of the island was below average for January, mostly in the 50 to 80% range. The gages along the two main mountain ranges had the highest totals for the month, with coastal and inland valley locations among the lowest. Interestingly, though, the sites that turned in above average totals for the month were in these relatively drier areas. This is most likely due to the way in which the convective shower bands set up, as well as the dominant southerly direction of the winds during the January rain events. The highest total for the month came from the USGS Poamoho RG 1 gage with 12.05 inches, (66% of average). The top daily total for Oʻahu this month came from the USGS Kahana Stream RG with 2.43 inches on the 3rd.

Maui County: [Maui January 2026 map] [Molokaʻi/Lanaʻi January 2026 map]

All but two sites across the county were below average for January, with the windward slopes and higher terrain around 50 to 80% of average. The two sites that came in above average for the month were Puʻu Aliʻi (second highest total for the county) and Lanaʻi City. The driest areas were in the central valley of Maui, and most other leeward areas of the county with around 20 to 40% of average. Note: several sites on Maui are still missing for the month due to maintenance issues. The USGS W. Wailuaiki Stream site on Maui held the top spot for monthly total with 15.98 inches (80% of average) and the highest daily total with 3.22 inches on the 5th.

Island of Hawaiʻi: [January 2026 map]

Portions of the island finally got some significant rainfall during January. The main beneficiaries were the Hilo, Puna, and Kaʻu Districts, thanks to a kona low early in the month. Most of the gages in these areas came in near to above average for the month. The Kealakomo RAWS site recorded its wettest January on record (since 2010). The remaining areas of the island were well below their January averages, mostly under 50%, primarily due to the prevailing southeasterly wind direction and fronts generally not holding together long enough to make it that far down the island chain. The highest monthly total for January came from the USGS Honoliʻi Stream rain gage near Hilo with 19.74 inches (115% of average). This site also had the highest daily total for the island and the state with 9.25 inches on the 5th.

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: December 2025

Prepared: January 8, 2026

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

Headline: A tale of two halves of the state: Rainy Kauai and Oahu with dry Maui County and the Big Island. Plus, some interesting calendar year stats.

December began with dry and stable conditions, as light southeasterly winds and localized land and sea breezes prevailed ahead of an approaching front. That weak front stalled near Kauaʻi on the 3rd, bringing showers embedded in southerly flow to Kauaʻi and Niʻihau into the 4th. High pressure rebuilt northeast of the state as the front retreated back to the west, allowing east to east-southeasterly trade winds to strengthen, with typical scattered windward and mauka showers. Winds weakened and veered southeasterly to southerly again around the 8th and 9th as another front approached. The front brought a wetter pattern statewide through the 11th, followed by cooler northerly winds in its wake.

The most significant weather of December occurred around mid-month. A stronger front approached on the 12th, bringing breezy south to southwest winds and pre-frontal showers. The front moved through Kauaʻi and Oʻahu on the 13th and 14th before stalling and retrograding westward through the 15th. After a brief lull on the 16th, a shortwave trough destabilized the atmosphere through the 20th, leading to another extended period of steady rainfall over Kauaʻi and Oʻahu. Combined totals over the week were around 3 to 6 inches on Kauaʻi (locally up to 7 inches) and 4 to 8 inches on Oʻahu, with isolated amounts near 10 to 14 inches along the Koʻolau Range and northern Waiʻanae Mountains. Rainfall rates were mostly moderate though, with mainly urban roadway flooding impacts, many instances of which were exacerbated by poor drainage maintenance. Two water evacuations occurred on windward Oʻahu (Ahuimanu and Kaneohe), along with one water rescue in the Kalihi area of Honolulu. Maui County and the Big Island were largely spared from this event, remaining under drier southeast flow.

Trade winds gradually returned from the 21st to the 23rd, bringing more stable conditions. Moisture from a remnant front was pushed southward during this period, enhancing showers along windward slopes, with rainfall totals around 1 to 2 inches on most islands.

Drier and locally breezy trades prevailed through Christmas Eve and Christmas Day, followed by weakening winds and a shift back toward an east-southeasterly direction ahead of another front. The month ended with moderate trades and generally dry conditions. A brief surge of moisture on the morning of the 30th slightly enhanced windward showers, but no significant impacts were reported.

Island of Kauaʻi: [December 2025 map] [year-to-date map]

With the significant rain event around the middle of the month, nearly all sites on the island came out with near to above average rainfall for December and a few nearly double their usual amounts; a significant improvement over a relatively dry November. The USGS gage on Mt. Waiʻaleʻale, yet again, had the highest monthly total for the island of 31.47 inches (105% of average), as well as the highest daily total for the island and state with 6.58 inches on the 23rd.

Aside from a few significant rain events, 2025 was pretty dry for Kauaʻi. Other than a handful of sites that ended the year above average, the remainder of the island below average (generally near or below 85%). The southern coast fared the worst, with only around half of their usual yearly rainfall. A handful of sites went down due to maintenance issues for the last few months of the year, resulting in no YTD numbers available. The Mt. Waiʻaleʻale gage took the top spot for YTD rainfall on the island and statewide with 319.65 inches (81% of average).

Island of Oʻahu: [December 2025 map] [year-to-date map]

Oʻahu joined Kauaʻi in benefitting from a few noteworthy rain events, with all but 4 sites coming in above average (several around 200%), including notoriously dry leeward areas. The sites that were below average, however, were still in the 80-90% range. The highest total for the month came from the USGS Poamoho RG 1 gage with 16.41 inches, (81% of average). The top daily total for Oʻahu this month came from the USGS Moanalua RG with 4.07 inches on the 14th.

Oʻahu finished the year in decent shape, with most sites near or above 75% of average (including a few spots just over 100% - most notably Mililani). The higher terrain sites in the Koʻolau range were unsurprisingly the top overall performers in terms of totals for the year. The Poamoho RG1 gage has the crown for the highest YTD total with 158.75 inches, (70% of average).

Maui County: [Maui December 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi December 2025 map] [year-to-date map]

Maui County struggled mightily in December, being left out of the main rain events, with all sites below average for the month and all (except for one on Lānaʻi at 75%) at or below 50% of average. The driest areas were in the central valley of Maui, with percentages in the single digits. Note: several sites on Maui are still missing for the month due to maintenance issues. Somewhat surprisingly, though, none of the sites had their driest December over the last few decades. The USGS’ Puʻu Kukui gage on Maui held the top spot for highest monthly total with 9.00 inches (only 30% of average). The highest daily total for the county goes to the USGS’s W. Wailuaiki Stream site with 3.58 inches on the 23rd.

All but one site in Maui County rounded out the year below average for rainfall, mainly 50 to 80%. The one exception was the Kula Branch Station on Maui with 120% of average. The USGS’ West Wailuaiki Stream gage is the winner with the county’s highest YTD total of 160.59 inches, (71% of average).

Island of Hawaiʻi: [December 2025 map] [year-to-date map]

The majority of the island was below average (under 50%) for December, due to missing out on rainfall from frontal passages. The Kawainui Stream gage recorded its driest December on record (since 2010) – the second driest December was just last year in 2024). The Hilo Airport had its driest December in the last 35 years (driest was 2024). However, the deep tropical moisture and southerly winds ahead of a couple of these fronts allowed some unseasonably high rainfall (2-3 inches over the course of the month) to fall over portions of the Kona Districts where several sites between Hōnaunau and the Kona Airport came in above average. The highest monthly total for December came from the USGS Honoliʻi Stream rain gage near Hilo with 7.88 inches, though only 46% of their monthly average. The highest daily total came from the Saddle Road Quarry gage with 5.16 inches on the 14th.

Overall, the Big Island had an extremely dry 2025. In fact, seven sites in the Hāmākua and Hilo Districts turned in their driest calendar years in their respective periods of record, most notably the Hilo Airport with its driest year since 1949 (2nd driest was 2010). The rest include: the NWS gage at Kamuela (since 1997), the NWS gages at Laupahoehoe, Mountain View and Waiakea Uka (since 1991), the University of Hawaiʻi’s Waiakea Experimental Station (since 2010), and the Waimea Plain NRCS SCAN site (since 2012). The Hakalau RAWS had its 2nd driest calendar year since 2004. Elsewhere, YTD values were generally 30 to 70% of average for the year. However, the beneficial rainfall over the summer helped to keep portions of the Kona and Kohala Districts above average for the year. The Kawainui Stream rain gage held the position for highest YTD total with 112.32 inches (83% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: November 2025

Prepared: December 3, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

Headline: Significant rainfall on Kauai, Maui, and the Big Island from a couple of notable events, but continued dryness for most leeward areas.

The month opened with dry and breezy conditions, though winds weakened and shifted slightly east-southeast as a front approached from the northwest. An upper low near the islands helped enhance windward and mauka showers through the first weekend, especially across the western islands and parts of the South Kohala District on the Big Island. The most notable rainfall occurred on the northern coast of Kauaʻi on the 2nd, where Flood Advisories were issued as rates reached 1 to 2 inches per hour for a large portion of the day. The NWS Hanalei gage measured around 10 inches in eight hours (11.2 inches in 24 hours), but the area, surprisingly, experienced no significant impacts. Tropical moisture also brushed the southern Big Island on the 3rd, producing heavier showers along windward slopes. A quieter stretch followed for the next few days, as moderate to locally breezy trades returned and conditions dried out. Only minimal windward showers developed, while a departing upper low spread high clouds over the state.

A cold front brought a more significant rainfall event on the 8th and 9th. Shallow moisture and low-level northeasterly flow favored windward and mauka areas for rainfall, where two-day totals commonly reached 1 to 3 inches. A few standout locations on each island recorded 5 to 9 inches, including West Wailuaiki on Maui and Puʻu Aliʻi on Molokaʻi. No flooding impacts were reported, and breezy northeast trades filled in behind the front. Typical breezy to locally strong trades dominated the 10th through the 14th, with lingering post-frontal moisture sustaining frequent windward showers. Maui County and the Big Island saw repeated daily rainfall totals of 1 to 3 inches, while Puʻu Kukui on Maui recorded isolated maxima over 7 inches on the 12th and 13th.

The middle of the month turned noticeably drier as moderate trades prevailed from the 15th to the 17th. A more humid and unsettled pattern returned from the 18th to the 20th when an upper low southwest of the islands pulled deep tropical moisture northward. With precipitable water values near 2 inches, enhanced showers developed mainly across the eastern half of the state. Breezy to locally windy trades focused the heaviest rainfall along windward slopes of Maui and the Big Island, where 24-hour totals generally reached 1 to 3 inches.

Conditions dried out and stabilized to close out the month, resulting in reduced shower activity with rainfall largely confined to scattered windward and mauka showers and otherwise quiet conditions. Trades also eased from moderate-breezy to light-moderate and shifted more out of the east-southeast as fronts passed north of the islands.

Island of Kauaʻi: [November 2025 map] [year-to-date map]

The island experienced a couple of days of island-wide heavy rainfall during the first half of the month, but it was not enough to keep island totals from coming in largely below average again and even drier overall than October. The leeward coast was especially dry in November, with many stations only in the single digits for percent of average. The gages at Hanapepe (since 1993) and Waimea Heights (since 2010) recorded their driest November. Port Allen came within 0.01 inches of tying its driest November since 2004. The exception to the dryness was the northern coastal areas and central higher elevations which came in near to above average including the NWS gage at Hanalei with 188% of their November average rainfall. The USGS gage on Mt. Waiʻaleʻale, yet again, had the highest monthly total for the island of 32.08 inches (85% of average). The highest daily total for the island (and the state as a whole), however, belongs to the NWS’ Hanalei gage with an impressive 11.20 inches on the 2nd.

The somewhat drier month brought the year-to-date (YTD) percents of average down a few points for November, though the higher elevations and northern coast remain near to above average for the year so far. The Mt. Waiʻaleʻale gage still holds the highest YTD total for the island and statewide with 288.18 inches (holding at 79% of average).

Island of Oʻahu: [November 2025 map] [year-to-date map]

With the exception of the sites in the higher elevations of the Koʻolau Mountains coming in near to above average for November, Oʻahu continued to hover below around 60% of average for monthly rainfall. The highest total for the month came from the USGS’ Tunnel RG site with 16.40 inches, (boosting them to 123% of average). This gage also took the top daily total for Oʻahu this month with 4.44 inches on the 9th.

The Oʻahu YTD values have generally come down a few percentage points from October, though the higher terrain sites were still near to above average and the rest of the island around 50 to 80% of average. The Poamoho RG1 gage retained the highest YTD total for the island with 142.34 inches, (69% of average).

Maui County: [Maui November 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi November 2025 map] [year-to-date map]

Several sites on Maui are still missing for the month due to maintenance issues, but the majority of the remaining gages across the county continued their below average trend for another month (70% or less). A few sites along the windward slopes of Haleakalā, Mauna Kahālāwai (West Maui Mountains), and Molokaʻi did manage to come in above average, thanks to several days of significant moisture-laden trade winds. The driest areas were still leeward, as well as the central valley of Maui and leeward Molokaʻi, with percentages of average even lower for November. The USGS’ Puʻu Kukui gage held the top spot for highest monthly total, as well as unseating Mt. Waiʻaleʻale for the state highest total, with 37.66 inches (126% of average). However, the highest daily total for the county goes to W. Wailuaiki Stream with 7.55 inches on the 9th.

The YTD percentages of average were largely the same as October, with the majority of sites between 60 to 90%, though a few spots in Upcountry Maui managed to remain above average for the year so far. The USGS’ West Wailuaiki Stream gage remains on top with the county’s highest YTD total of 153.59 inches, upping them to 73% of their YTD average.

Island of Hawaiʻi: [November 2025 map] [year-to-date map]

The majority of the island was below average again for November. However, significant rainfall during the middle of November helped to boost the percentages up, most significantly over the higher elevations of the Kona, Kohala, Hāmākua, and Hilo Districts where several sites came in well above average. With a bit of an early Kona District dry season surprise, the Waikoloa rain gage recorded its wettest November since 2010 (200% of average). The highest monthly total for November came from the Honoliʻi Stream rain gage near Hilo with 19.17 inches, boosting them to 78% of average. The highest daily total, though, came from the Saddle Road Quarry gage with 5.16 inches on the 14th.

The beneficial rainfall this month helped to increase the YTD percents of average for a few spots in the higher elevations, though the remainder of the island remained around the same values from the end of October (Kona District and portions of the Kohala District around 100 to 150% and around 30 to 70% elsewhere). The Kawainui Stream rain gage held the position for highest YTD total with 108.19 inches (now 89% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: October 2025

Prepared: November 4, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

Headline: October rainfall still largely below average state-wide, despite a better showing for Oʻahu and Big Island over September’s amounts.

The month began with moderate trades and increased moisture, bringing enhanced windward showers, especially on Oʻahu and Molokaʻi. As high pressure weakened between the 2nd and 5th, trades shifted southeast and lightened, allowing land and sea breezes to form. This shifted shower activity to interior and upslope areas, mainly southeast-facing slopes, though rainfall stayed generally light (around a quarter inch or less).

A weakening surface trough lingered over the western half of the state from the 6th to the 10th, bringing higher humidity and periods of light to occasionally moderate showers, most notably on Kauaʻi where isolated totals reached 1 to 2 inches. Light southeasterly winds supported localized heavy rainfall over the southern coastal and upslope areas of Kauaʻi and Oʻahu during this time. A Flood Advisory was issued for the island of Oʻahu for rainfall rates of 1 to 2 inches per hour. Moisture decreased after the 11th, though light winds continued to support afternoon inland showers through the 14th.

Moderate to breezy trades returned mid-month along with an upper low near Kauaʻi, producing several days of wetter weather from the 16th into the 21st. Heavy rain prompted the issuance of a Flood Advisory on the Kona slopes of the Big Island on the 16th for rainfall rates of up to 1 inch per hour and for the island of Kauaʻi on the 17th for rates of 1 to 2 inches per hour. A drying trend took hold from the 22nd to 24th as trades strengthened into the breezy to locally strong range, leading to periods of critical fire weather conditions across interior and leeward zones.

Deep tropical moisture was drawn northward into the Big Island beginning on the 24th and spread westward across the state. The heaviest rainfall occurred over windward areas of the Big Island and Maui, while cold temperatures aloft allowed for wintry precipitation on the Big Island summits. Some leeward and higher terrain areas received 1 to 2 inches of rain, prompting a Flood Advisory for Kauaʻi during early morning on the 28th. Trade winds weakened again over the last few days of the month as a front lingered well north of the state. On the 29th, enhanced showers from lingering instability from an upper trough brought heavy rainfall to the Big Island from Hilo around South Point to Kona, triggering a Flood Advisory. Conditions trended drier to close out the month under light to moderate trades.

Island of Kauaʻi : [October 2025 map] [year-to-date map]

The island experienced a couple of days of island-wide heavy rainfall during the second half of the month, but it was not enough to keep island totals from coming in largely below average for October. The exception was the central higher elevations which came in near average. The standout area was the north-central portion of the island, where the NWS gage at Hanalei reported 131% of their October average rainfall. However, western and southern portions of the island picked up some beneficial rain due to a period of moist, southerly flow. The USGS gage on Mt. Waiʻaleʻale, yet again, had the highest monthly total (for the island and statewide), of 24.01 inches (71% of average), and the highest daily total on the island of 2.78 inches on the 17th.

The year-to-date (YTD) totals brought the percents of average down a few points for October, but continued the September distribution with about half of the sites near to above average and the remaining ones mainly in the 60% to 85% range for the year so far. The Mt. Waiʻaleʻale gage still holds the highest YTD total for the island and statewide with 256.10 inches (holding at 79% of average).

Island of Oʻahu: [October 2025 map] [year-to-date map]

With the exception of a few sites in the central portion of the island coming in above average for October, Oʻahu continued to hover below around 60% of average for monthly rainfall. The highest amounts were again in the higher elevations of the Koʻolau Mountains, though, along with Kauai, many leeward areas got in on some beneficial rain during southerly flow. The highest total for the month again came from Poamoho RG1 with 8.99 inches, (46% of average). This gage also took the top daily total for Oʻahu this month with 1.43 inches on the 7th.

The Oʻahu YTD values have generally come down a few percentage points from September, though the higher terrain sites were still near to above average and the rest of the island around 50 to 80% of average. The Poamoho RG1 gage had the highest YTD total of 129.65 inches, though their YTD value dropped a bit further to 70% of average.

Maui County: [Maui October 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi October 2025 map] [year-to-date map]

Several sites on Maui are still missing for the month due to maintenance issues, but the majority of the remaining gages across the county continued their below average trend for another month (70% or less). A few sites did manage to come in near average, with one on Molokaʻi just above average. The driest areas were still leeward, as well as the central valley of Maui, as well as leeward Molokaʻi, though the percentages there for September did improve. The USGS’s Kepuni gage recorded the driest October in its 15-year period of record. On a positive note, Upcountry Maui got some much-needed rainfall and were able to downgrade their water shortage from level 3 to level 2. The USGS’ Puʻu Kukui gage held the top spot for highest monthly total with 12.70 inches (49% of average), and highest daily total for the county of 3.58 inches on the 18th. Their daily total also unseats Mt. Waiʻaleʻale for highest in the state for October.

The YTD percentages of average held steady again in October, with the majority of sites between 60 to 90%. Upcountry Maui is still riding high from some good totals in September and October, coming in above average for the year so far. The USGS’ West Wailuaiki Stream gage remains on top with the county’s highest YTD total of 123.55 inches (65% of their YTD average).

Island of Hawaiʻi: [October 2025 map] [year-to-date map]

The majority of the island was below average again for October, though the island as a whole received a good deal more rain than September. This helped to boost the percentages up, most significantly over the interior higher elevations as well as portions of the Hāmākua, Hilo and Puna districts. The leeward coast/slopes of the Kohala and Kona districts turned in another month of near to above average rainfall. The highest monthly total for October came from the Honoliʻi Stream rain gage near Hilo with 10.75 inches (60% of average). This site also recorded the highest daily total on the island of 2.21 inches on the 25th.

Despite the good showing from interior and windward Big Island, very little change to the YTD percent of average occurred from September to October. The Kona district and portions of the Kohala district are still running 100 to 150% of average for the year so far, while the remainder of the island is holding around 30 to 70%. The Kawainui Stream rain gage held the position for highest YTD total with 89.39 inches (79% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: September 2025

Updated: October 4, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

Headline: September rainfall improved upon August’s dismal showing, especially for Kauaʻi, though many parts of the state remain significantly below average for the year so far.

September opened with lingering moisture and a mid-level low northwest of Kauaʻi, which produced enhanced showers on the 1st. The Big Island’s Kona district was hit hardest, with 0.75 to 1.25 inches common and up to 3+ inches at Waiaha Stream near Kailua-Kona, prompting a Flood Advisory for those areas. Smaller totals were observed in the Waiʻanae Mountains of Oʻahu (up to 0.5 inches) and across Kauaʻi (0.25 to 1+ inches). Light to moderate trades and drier, more stable conditions returned through the 3rd with modest windward and mauka showers and mostly dry leeward areas, except for afternoon showers along the Big Island’s leeward slopes. By the 6th, a trough north of the islands further weakened the trades, allowing land and sea breezes to take over and ushering in warm, muggy weather.

The second week featured deep tropical moisture from former Tropical Cyclone Kiko, which spread across the state between the 8th and 11th. Most locations received 0.25 to 1 inch of rainfall, while windward Maui and the Big Island were the wettest, picking up 1 to 2 inches on the 11th. The following week saw a return to drier weather with moderate to locally breezy trades. Showers were light and mainly confined to windward slopes, aside from a minor uptick in shower coverage/amounts when weak troughs crossed the islands on the 12th.

Moisture from a weakening front combined with instability from an upper low to produce enhanced showers between the 18th and 22nd with the most notable rainfall over the western half of the state. However, the Kona coast of the Big Island also received 0.75 to 2+ inches on the 21st, resulting in another Flood Advisory that evening.

Trade winds then weakened as a low northeast of the islands shifted winds out of the east-southeast between the 23rd and 26th. Southeast Kaʻū picked up some much needed rainfall on the 24th, enough to trigger a Flood Advisory. By the 25th and 26th, land and sea breezes had become established, leading to light showers in interior and leeward areas. Kauaʻi, however, was the standout, recording widespread 0.75 to 2 inches and nearly 3 inches in some interior spots, which prompted a Flood Advisory on the 26th. The month closed with a rebuilding trade wind pattern, which stabilized the atmosphere, keeping showers light and focused on the state’s windward areas and the Kona side of the Big Island.

Island of Kauaʻi : [September 2025 map] [year-to-date map]

Rainfall totals were largely near to above normal for September. The typically dry leeward areas all came in above their monthly averages, with a few spots in the northwest portion of the island reaching 2 to 3 times higher. This was mainly the work of a few days of heavy rain near the end of the month, but still gave these areas some much needed.  The USGS gage on Mt. Waiʻaleʻale, once again, had the highest monthly total (for the island and the state as a whole), of 20.28 inches (67% of average), and the highest daily total of 3.10 inches on the 26th.

Significant September rainfall helped to make up some of the summer deficit, though only about half of the sites were near to above average to end the dry season. The remaining year-to-date (YTD) totals are mainly in the 60% to 85% range. The Mt. Waiʻaleʻale gage still holds the highest YTD total for the island and the state as a whole with 232.09 inches (79% of average).

Island of Oʻahu: [September 2025 map] [year-to-date map]

Oʻahu also got in on the good September rainfall, though not nearly to the extent of Kauaʻi. All but two sites came in below average for the month, but most improved upon their August values by around 20%. Leeward areas and the windward coast are still struggling, with most sites less than 25% of average for the month, aside from the Honolulu and Kalaeloa airports which received amounts that were 81% and 67% of average, respectively. Mānoa Lyon Arboretum also had the second driest September in their 109-year period of record (driest was in 1975). Moanalua RG and Tunnel RG had their driest Septembers since 2010 and 2013, respectively. The Waiʻanae-Kawiwi gage had their driest September since 1991. The highest amounts were again in the higher elevations of the Koʻolau Mountains, though many of these were still only around 25% to 50% of their September averages. The highest total for the month again came from Poamoho RG1 with 4.74 inches, though only 26% of average. Despite being the top performer on Oʻahu, Poamoho RG1 turned in its driest September since 2012. The Pūpūkea Rd. RG took the top daily total spot this month with 1.25 inches on the 25th.

The Oʻahu YTD values have come down a few percentage points from August, though windward and mountain sites were still near to above average and leeward sites around 50 to 80%. The Poamoho RG1 gage had the highest YTD total of 120.66 inches, though their YTD value dropped to 73% of average.

Maui County: [Maui September 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi September 2025 map] [year-to-date map]

A few sites on Maui are missing for the month due to maintenance issues, but the remaining gages continued their below average trend for another month. Aside from a handful of sites in Upcountry Maui/Haleakalā slopes which were near or above average, sites were below average for the month county-wide. The driest areas were still the central valley and leeward West Maui, as well as leeward Molokaʻi, though the percentages of average for September were generally higher than for August. The USGS’ Puʻu Kukui gage unseated the West Wailuaiki Stream gage for the highest monthly total with 6.18 inches (only 28% of average), and the highest daily total of 2.18 inches on the 11th.

The YTD are holding steady again in September, with the majority of sites at 60% or higher. However, leeward areas and the Maui central valley are still limping along with 50% to 60% of their YTD averages. Despite having the second highest monthly total, the USGS’ West Wailuaiki Stream gage remains on top with the county’s highest YTD total of 112.91 inches, but drops them a bit to 66% of their YTD average.

Island of Hawaiʻi: [September 2025 map] [year-to-date map]

The entire island was below average for September, with the seasonable exception of the leeward coast/slopes of the Kohala and Kona districts which turned in another month of near to above average rainfall. The Hāmākua, Hilo (mainly coastal), and Puna districts continues to be the driest. Despite upping their % of average values for September by up to 10%, most sites were still only about 30 to 40%. The Kulani NWR gage had the driest September in its 14-year period of record. The highest monthly total for September came from the rain gage at Waiaha Stream (Kona district slopes) with 9.41 inches (175% of average). This site also recorded the highest daily total on the island of 3.64 inches on the 1st, which unseats Mt. Waiʻaleʻale as the highest daily total for the state this month.

Very little change to the YTD percent of average occurred from August to September, with the Kona district and portions of the Kohala district still running 100 to 150% of average for the year so far. The Kawainui Stream rain gage held the position for highest YTD total with 79.86 inches (74% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: August 2025

Updated: September 3, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

The theme for August is “Dry, Drier and Driest.” Aside from a few modest rainfall events helping to boost a few sites to average or above, the majority of the state came in with below average totals for the month, including around a quarter of the gages in this summary with their driest August on record. Breezy to locally windy trades began the month, before easing to light to moderate speeds over the next couple of days. Aside from light windward showers on the 2nd and 3rd, most areas remained dry.

On the 6th, humid conditions developed as the remnants of Tropical Cyclone Gil passed north of the islands, disrupting the trades and allowing land/sea breezes. Moisture brought 0.25 to 0.5 inches of rain over windward and some leeward slopes, including up to 0.3 inches in the drought-affected Kaʻū district of the Big Island, as well as the coast and leeward slopes of Haleakalā on Maui. Trades and drier weather returned from the 7th to the 9th. On the 10th and 11th, Tropical Cyclone Henriette passed by to the north, bringing light winds, humid conditions, and only isolated showers.

Moderate to breezy trades resumed for the 12th through 24th, with lower humidity and limited windward showers. The only exceptions to this were a low-level trough on the 14th/15th and the remnants of Tropical Storm Ivo through the 18th, which both provided brief increases in clouds and showers to portions of the state.

Between the 25th and 27th, a stalled surface low north of the islands created a hybrid pattern of east-southeast trades and land/sea breezes. This produced showers along east and southeast-facing slopes of Hawaiʻi Island, while the rest of the state stayed mostly dry. From the 28th to 31st, another trough kept winds light to moderate with leeward sea breezes. The Kona coast saw the most rain to start, with 0.25 to 1 inch on the 28th (up to 2.5 inches in spots) and 0.75 to 1 inch on the 29th. A surge of deep tropical moisture, associated with a trough passing by just south of the islands on the 30th and 31st, increased showers statewide, bringing 0.33 to 0.75 inches to windward terrain on Kauaʻi, Oʻahu, Maui, and Hawaiʻi Island (including some areas currently in severe drought), with over 1 inch in the Koʻolau Mountains of Oʻahu.

Island of Kauaʻi : [August 2025 map] [year-to-date map]

Rainfall totals were all below average, with all but one site only around 50% of average or less for August. The highest amounts were all in the higher terrain and windward slopes of the island in the 30 to 50 % range, while leeward areas struggled to break 20% of their August averages. A total of 6 sites on Kauaʻi turned in their driest August on record: Mt. Waiʻaleʻale (since 2003), Hanalei (since 1991), Kilohana (since 2010), Mōhihi Crossing (since 2008), Puʻu Opae (since 2010), Waiʻalae RG (since 2010) The USGS gage on Mt. Waiʻaleʻale, once again, had the highest monthly total, though only a meager 12.73 inches (37% of average), and the highest daily total of 2.77 inches on the 19th. This site’s monthly and highest daily totals were also the highest across the entire state for August.

Despite the poor August showing, a handful of sites managed to stay above average for the year so far, mainly due to good winter rainfall earlier in the year. The remaining year-to-date (YTD) totals are mainly in the 50% to 80% range, with a few spots on the southern coast as low as 33%. The Mt. Waiʻaleʻale gage continues to have the highest YTD total for Kauaʻi County and the state as a whole with 211.81 inches, though a dry August brought their YTD average down to 81%.

Island of Oʻahu: [August 2025 map] [year-to-date map]

The story of dryness was much the same on Oʻahu, with all sites near or below 50% of average (below 20% for leeward areas) for August. A whopping 20 sites recorded their driest August on record! The most notable of these are the Honolulu Airport (tied record from 1944 and 1974), Punaluʻu Pump (since 1913), and the following sites since 1991: Moanalua Stream, Niu Valley, Waipiʻo, and Palolo Fire Station. The highest amounts were again in the higher elevations of the Koʻolau Mountains, though many of these were still only around 30% to 50% of their August averages. The highest total for the month again came from Poamoho RG1 with 3.41 inches, but was a paltry 19% of their August average.

The Oʻahu YTD values remain largely unchanged from July, though, with windward and mountain sites still near to above average and leeward sites around 50 to 80%. The Poamoho RG1 gage had the highest YTD total of 115.92 inches, though their August value brought them down to 79% of their average for the year so far.

Maui County: [Maui August 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi August 2025 map] [year-to-date map]

All but a few sites on the island were below 40% of average for the month, with the driest areas being the central valley and leeward West Maui, as well as leeward Molokaʻi (in the single digits to teens percent of average). The Haʻikū gage had its driest August since 1991. Kīhei 2 and ʻUlupalakua Ranch were the two outliers, coming in with 433% and 123% of their August averages. This, however, was due to heavy pop-up showers over leeward Haleakalā on the 6th, which served to skew the percentages above average. Kealia Pond recorded zero rainfall for the fourth month in a row. The USGS’ West Wailuaiki Stream gage had the highest monthly total for the third month in a row with 4.47 inches (only 26% of average), and the highest daily total of 0.93 inches on the 17th.

The YTD are holding steady again in August, with the majority of sites at 60% or higher. However, leeward areas and the Maui central valley are still limping along this year so far with 50% to 60% of their YTD averages. The USGS’ West Wailuaiki Stream gage remains on top with the county’s highest YTD total of 108.47 inches, but drops them a bit to 69% of their YTD average.

Island of Hawaiʻi: [August 2025 map] [year-to-date map]

Nearly the entire island was below average for August, with the seasonable exception of the leeward coast/slopes of the Kohala and Kona districts which turned in another month with many sites near to above average. The higher elevations of the interior joined the rest of the Kaʻū and Hāmākua districts as being the driest areas, failing to exceed 25% of their August averages. The windward coasts of the Hilo and Puna districts also struggled to top around 30% of average. 10 stations recorded their driest August on record: Waiākea Exp. Station (since 2010), Hakalau (since 2011), and Hilo Airport (since 1949) had their driest August on record. Kūlani NWR (since 2012), Kaʻūpūlehu (2010), Hakalau (tied-since 2010), Laupāhoehoe (1991), Mountain View (1991), Puʻu Aliʻi (2012), Piʻihonua (1991), Saddle Quarry (2010), Waiākea Exp Station (2010), and Waiākea Uka (1991) The highest monthly total again came from the USGS gage at Kawainui Stream with 10.09 inches (113% of average). This site also recorded the highest daily total for the month of 1.37 inches on the 3rd.

The YTD percent of average highs and lows were similarly distributed to the monthly numbers, though the Kona district and portions of the Kohala district are still running 100 to 160% of average for the year so far. The Kawainui Stream rain gage held the position for highest YTD total with 74.28 inches (74% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: July 2025

Prepared: August 5, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

July began with a typical summer trade wind pattern dominated by high pressure to the north and stable conditions aloft. Moderate to locally breezy trades brought generally dry weather through the 4th, with only modest windward and mauka showers. Leeward areas were mostly dry, aside from light afternoon rainfall on the Kona and Haleakalā slopes. From the 5th through the 8th, a strengthening ridge aloft led to breezy to locally strong trade winds, a lower inversion height and very dry conditions, with a few brush fires igniting in Māʻili, upslope Nānākuli, and Kunia Village on leeward Oahu. Despite the dry conditions, the Hilo and North Kohala districts on windward Big Island were able to tally up to 1.25 inches on the 7th in a few spots.

Between the 9th and 13th, a weakening of the ridge allowed the inversion to lift slightly. Bands of deeper moisture moved in on the 11th and 12th, enhancing windward and mauka showers with totals reaching up to 1.5 inches in interior and windward Oʻahu. A surface trough passed through the state from 14th to the 15th, temporarily lifting the inversion and allowing for some enhanced shower activity, mainly over windward higher terrain and portions of the North Kohala coast and windward slopes between Pololū Valley and Waipiʻo Valley on the Big Island. A mid-level ridge returned through the 18th, stabilizing the atmosphere and generally reducing rainfall. However, a moisture surge on the 17th brought increased windward and upslope showers, especially for Maui and the Big Island, where the Kona slopes between Kailua-Kona and Kealakekua received 0.75 to 1.5 inches of rain.

The most notable rain event occurred on the 19th and 20th due to a combination of above-average moisture and instability from a weak mid-level low northwest of Kauaʻi. Kauaʻi saw significant flooding, including road closures and elevated river levels, easily verifying the Flash Flood Warning issued the morning of the 20th. Mount Waiʻaleʻale recorded nearly 8 inches of rain in 24 hours. The Hanalei River rose above flood levels and crested at 11.78 feet, leading to the closure of Kūhiō Highway. Flooding was also reported near the mouth of the Wailua River.

Drier conditions returned from the 21st through 29th with ridging aloft and moderate to locally breezy trades. A weak surface trough brought some shower enhancement toward the end of that period, mainly affecting windward slopes with daily rainfall totals of 0.5 to 1.5 inches. The month ended with a dry, stable air mass and locally strong trades, bringing minimal rainfall.

Island of Kauaʻi : [July 2025 map] [year-to-date map]

Rainfall totals were mainly below average for Kauaʻi in July. The exception was in northern and central portions of the island, where the Hanalei and Waiahi gages received 126% and 100% of their monthly totals, respectively (mostly with the rain event on the 19th/20th). Leeward portions of the island turned in another dismal month with most sites only 20 to 30% of their July averages. The USGS gage on Mt. Waiʻaleʻale, once again, had the highest monthly total with 33.50 inches (86% of average), and the highest daily total of 6.46 inches on the 19th. This site’s monthly and highest daily totals were also the highest across the entire state for July.

Aside from a few (mainly south and east coast) sites in the 30 to 60% range, the majority of the year-to-date (YTD) totals are now around 70% of average or higher, with several inland sites running above average. The Mt. Waiʻaleʻale gage continues to have the highest YTD total for Kauaʻi County and the state as a whole with 199.08 inches, though still only 88% of their average through July.

Island of Oʻahu: [July 2025 map] [year-to-date map]

The higher elevations of the Koʻolau Mountains were consistently above average for July, with the Waiawa Correctional Facility coming in at nearly 2.5 times their monthly average. The lower slopes of both mountain ranges were generally in the 60-90% range, while the majority of the leeward coast struggled to reach 20% of their July averages. Several of these leeward gages also turned in some of their driest July totals on record. Sites with their driest July on record: Kamehame (since 1993) and Kulani NWR (since 2012). Niu Valley (since 1991) and Honoʻuliʻuli (since 2010) had their second driest July totals on record. The USGS’ Poamoho RG1 gage had the highest monthly total of 16.08 inches (89% of average) as well as the highest daily total of 4.04 inches on the 19th. This monthly total also gave the Poamoho RG1 gage its 2nd wettest July on record (since 2012).

The Oʻahu YTD values remain largely unchanged from June, with windward and mountain sites still near to above average and leeward sites around 50 to 80%. The Poamoho RG1 gage had the highest YTD total of 112.51 inches, maintaining 87% of their average for the year so far.

Maui County: [Maui July 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi July 2025 map] [year-to-date map]

Most sites were below average for the month, with the driest areas being the leeward coast of Haleakalā and central valley of Maui, as well as leeward Molokaʻi (in the single digits to teens percent of average). Kīhei 2 and Kealia Pond recorded zero rainfall for the third month in a row. For the most part, windward areas were able to rebound from a dismal June and get to 80% or higher of their July average rainfall, especially the eastern higher terrain of Molokaʻi, where the Puʻu Aliʻi and Kamalō gages recorded 196% and 121% of their July averages, respectively. The USGS’ West Wailuaiki Stream gage had the highest monthly total for the second month in a row with 17.03 inches (85% of average), and the highest daily total of 3.41 inches on the 19th.

The YTD are holding steady in July, with the majority of sites at 60% or higher. However, leeward areas and the Maui central valley are still limping along this year so far with only 30 to 50% of their YTD averages. The USGS’ West Wailuaiki Stream gage remains on top with the county’s highest YTD total of 104 inches, which improves them to 74% of their YTD average.

Island of Hawaiʻi: [July 2025 map] [year-to-date map]

Most windward and interior sites were below average for June, the worst of which were in the Kaʻu and Hāmākua districts, as well as leeward lower elevations of the Kohala district. These areas failed to exceed 25% of their July averages. Waiākea Exp. Station (since 2010), Hakalau (since 2011), and Hilo Airport (since 2010) had their driest July on record. Kealakomo (since 2010), Kamuela (since 1991), and Saddle Quarry (since 2010) had their second driest July on record. The highest totals for the month were again found in the higher elevations of the North Kohala district and the northern Kona district, though not as impressive as June and mostly just below average (70-100%). However, the Waiʻaha, and Kawainui Stream gages did manage to come in above average. The highest monthly total again came from the USGS gage at Kawainui Stream with 15.72 inches (117% of average). This site also recorded the highest daily total for the month of 1.37 inches on the 7th.

The YTD percent of average highs and lows were similarly distributed to the monthly numbers, though the Kona district is still running 110 to 190% of average for the year so far. The Kawainui Stream rain gage surpassed Honoliʻi Stream for the highest YTD total with 64.19 inches (70% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: June 2025

Prepared: July 7, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

June began with high pressure far to the northeast and a deep surface trough to the west of Kauaʻi drew in higher moisture with east-southeast winds. This led to active windward showers around Kauaʻi and Oʻahu and some sea breeze-driven showers on leeward Oʻahu between Honolulu and Nānākuli, with totals reaching up to 0.25 inches. The wettest windward spots, especially in the terrain of Kauai and Oʻahu, recorded between 0.5 to 1.5 inches of rainfall. The next couple of days were dominated by moderate to breezy trade winds and mostly dry conditions, with isolated to scattered windward and mauka showers.

Early morning showers returned June 4–5 along the Kona slopes of Hawaiʻi Island (2-day totals around 0.5–1 inches). A decaying front and upper disturbance enhanced rainfall across windward areas on the 6th, enhancing windward and mauka showers, with rainfall up to 1.5 inches in some areas, and around 2 inches at Mt. Waiʻaleʻale. Weaker trades and sea breezes on the 7th and 8th led to afternoon showers along Kona slopes (0.10 to 1.25 inches, and up to 2 inches near Kealakekua on the 8th), with light rainfall in interior Kauaʻi and Maui. Elsewhere, upper-level troughing and stable mid-levels brought little more than high clouds and minimal additional. Light to moderate trades persisted on the 9th and 10th, with a surface trough west of Kauaʻi and weakening inversion delivering increased moisture and windward showers, mainly over Kauaʻi and Oʻahu.

Trades strengthened to locally breezy June 11th through the 17th as high pressure built north of the state. Most areas remained dry during this stretch, though a few shallow moisture bands brought scattered windward and mauka showers.  Gages recorded up to 0.25 inches on the night of the 12th to 13th (highest totals on Hawaiʻi Island and Maui), with widespread showers (0.25 to 0.75 inches, locally near 1 inch) across the islands on the night of the 16th into the 17th. Beginning on the 18th, trades weakened slightly as the high shifted eastward. Moderate showers fell on the Kona slopes (0.25–1 inches) through the 20th. Trades returned to breezy-to-locally-strong by the 21st with minimal rainfall statewide.

A weak upper trough passed north of the islands June 23–25, enhancing windward/mauka showers. Kauaʻi saw the heaviest rain (up to 2.9 inches at Mt. Waiʻaleʻale), with 0.25–1 inches on Oʻahu and Maui, and 0.25–1.5 inches on Hawaiʻi Island. June closed with breezy trades and generally drier conditions. However, on the 30th, southeast winds allowed localized leeward/interior showers, including 0.1–0.5 inches over interior valley sites of Oʻahu (around Pearl Harbor), ~0.15 inches for leeward Kauaʻi, and up to 1 inches on the Kona slopes.

Island of Kauaʻi : [June 2025 map] [year-to-date map]

Rainfall totals were highly varied across Kauaʻi for the month of June. While the highest amounts occurred over the inland terrain, the leeward areas and northwest Kauaʻi coast were nearly all above average for the month, with the Mana gage over twice their June average. The exception was Hanapēpē with only 50% of their June average. The remaining areas were generally below average (around 50 to 70% of average). The USGS gage on Mt. Waiʻaleʻale, once again, had the highest monthly total of 33.33 inches (101% of average), and the highest daily total of 3.65 inches on the 16th. This site’s monthly and highest daily totals were also the highest across the entire state for June.

The year-to-date (YTD) totals are still 30 to 60% of average for leeward areas, while windward and interior terrain are near to above average so far. The Mt. Waiʻaleʻale gage continues to have the highest YTD total for Kauaʻi County and the state as a whole with 165.58 inches, though still only 88% of their average for the first half of the year.

Island of Oʻahu: [June 2025 map] [year-to-date map]

The majority of rainfall totals were below average, with the worst being the coastal areas, both windward and leeward. The exception to this were several interior valley sites from Kalaeloa to Schofield, which came in above average, mostly due to a couple of days of good rainfall during the last week of the month. Leeward slopes of Koʻolau Range had the highest totals again this month, though percent of average values were only in the 50 to 70% range. The Mānoa Lyon Arboretum Cooperative Observing Station had the highest monthly total of 11.42 inches (89% of average) as well as the highest daily total of 1.73 inches on the 2nd. The Kiʻi gage near Kahuku turned in its driest month on record (since 2005) for the second month in a row with only 5 percent of average for June. The NWS’s Ahuimanu Loop gage and the Makua Range RAWS site recorded their driest Junes on record (since 2004 and 2003, respectively).

The Oʻahu YTD values are still in decent shape though, windward and mountain sites still near to above average and leeward sites around 50 to 80%. The USGS’ Poamoho Rain Gage No. 1 had the highest YTD total of 96.43 inches, though June dropped them to around 87% of their average for the year so far.

Maui County: [Maui June 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi June 2025 map] [year-to-date map]

All sites (except Kamalō on SE Molokaʻi [almost 200% of average]) were below average for the month, with the driest areas being the leeward coasts and central valley of Maui and leeward Molokaʻi (in the single digits to teens percent of average). Kīhei 2 and Kealia Pond recorded zero rainfall for the second month in a row. Kahului Airport also had zero rainfall for June. Windward areas and Lanaʻi didn’t fare much better overall, with the wettest spots only receiving around 50 to 90% of their June averages. The USGS’ West Wailuaiki Stream gage had the highest monthly total of 11.64 inches (89% of average), and the highest daily total of 1.22 inches on the 27th. The site at ʻUlupalakua Ranch recorded its driest June since 2009, while the NWS gage at Kahakuloa had its driest June since 2010.

The YTD values fared a little better in June, with the majority of sites at 60% or higher, including leeward Maui (still near to above average, thanks to a wet January and April). The USGS’ West Wailuaiki Stream gage remains on top with the county’s highest YTD total of 86.97 inches, which improves them to 72% of their YTD average.

Island of Hawaiʻi: [June 2025 map] [year-to-date map]

Most windward and interior sites were below average for June, the worst of which were in the Hāmākua district and lower elevations of the Kohala district. The Kapāpala RAWS station recorded its 2nd driest June on record (since 2012). The highest totals were again found in the Kona district, with most sites exceeding their monthly averages, several with 2 to 3 times their average. The NWS gages at Hōnaunau No. 2 and Kealakekua, as well as the Waikoloa RAWS, all recorded their wettest Junes on record (since 1993, 1991, and 2010, respectively). The highest monthly total came from the USGS gage at Kawainui Stream with 14.94 inches (151% of average). This site also recorded the highest daily total for the month of 2.64 inches on the 23rd.

The YTD percent of average highs and lows were similarly distributed to the monthly numbers. The USGS’ rain gage at Honoliʻi Stream remains the highest YTD total with 48.63 inches (44% of average). The Kawainui Stream gage was a close second with 48.47 inches (62% of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Hydrology Program Manager
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: May 2025

Prepared: June 5, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

May was dominated by moderate to breezy trade wind conditions with a couple of upper-level disturbances that helped to enhance rainfall around the middle to latter portion of the month. The first week of May was marked by typical moderate to breezy easterly trade winds with scattered windward and mauka showers and limited rainfall across leeward areas. Weak troughing aloft helped provide modest instability to pockets of moisture moving in on the trades to enhance showers, mainly over windward areas on the 8th and 9th, though a few showers did make it over to select leeward areas. The Puʻu Kukui and West Wailuaiki Stream U.S. Geological Survey (USGS) rain gages on Maui recorded their highest daily totals for the month on the 8th at 2.56 inches and 1.13 inches, respectively. The modestly-enhanced rainfall was not enough to prevent a wildfire near Waimea Canyon (Kauaʻi) on the 7th and one near Honokaʻa in the Big Island’s Hāmākua district on the 11th.

Moderate to breezy easterly trade winds continued through the 16th, easing slightly and shifting out of the east-southeast through the 19th. As the winds weakened a bit, a complex upper-level disturbance developed over the state and lingered through 19th, for a weakening of the temperature inversion and enhancement to shower activity. The east-southeast direction of the wind allowed for afternoon sea breezes to develop in the wind-sheltered leeward and interior areas and gave them some much needed rainfall, especially on the Big Island. Flood Advisories were issued for the Kona districts of the Big Island on the 16th and 18th, and interior/leeward Oʻahu on the 17th. No significant flooding impacts were observed. The USGS’s Mt. Waiʻaleʻale gage recorded its (and the state’s) highest daily rainfall total of 8.48 inches on the 18th. Another upper-level low moved over the area from the northwest on the 22nd and 23rd, enhancing trade wind showers mainly over windward and mauka areas.

Moderate to locally breezy trade winds and drier conditions prevailed over the Memorial Day weekend due to increasing atmospheric stability and decreasing moisture. Mostly dry trade wind conditions continued through the end of the month, with wind speeds decreasing slightly as high pressure north of the state shifted southward and weakened. A notable exception to the dry conditions was the USGS Kilohana Rain Gage #1 on the northern slopes of interior Kauaʻi which recorded its highest daily rainfall total for the month at 2.44 inches, likely due to sea breeze enhancement under weaker trade winds.

Island of Kauaʻi : [May 2025 map] [year-to-date map]

May rainfall totals were generally near to above average (85 to 150 percent of average) across interior and northern Kauaʻi, while locations along the southern and east coasts were all below average (around 40% of average or less). The USGS gage on Mt. Waiʻaleʻale had the highest monthly total of 39.34 inches (128 percent of average), and the highest daily total of 8.48 inches on May 16. This site’s monthly and highest daily totals were also the highest across the entire state for May. The USGS Kilohana Rain Gage #1 came in second place for the month with 17.89 inches (149 percent of average).

The overall lack of significant rain events in May kept the majority of sites on Kauaʻi around the same year-to-date (YTD) percent of average as they were at the end of April. The Mt. Waiʻaleʻale gage continues to have the highest YTD total for Kauaʻi County and the state as a whole with 135.25 inches, though this amount is still only 85 percent of their average for the first 5 months of the year.

Island of Oʻahu: [May 2025 map] [year-to-date map]

The majority of the Oʻahu rain gages posted below average totals for the month of May, the worst of which were along the leeward and north coastal areas. Gages along the Koʻolau Range (especially the leeward slopes) had the highest totals, ranging from around 7 to 12 inches and some sites up to 2 times their May averages. The remainder of the windward areas were generally 60 to 80 percent of average for May. The USGS’ Poamoho Rain Gage No. 1 had the highest monthly total of 14.97 inches (86 percent of average), and the highest daily total of 3.85 inches on May 17. The Kiʻi gage near Kahuku turned in its driest May on record (since 2005) with only 18 percent of average for May.

The Oʻahu YTD percentages of average suffered slightly from the relatively dry May, though most of the gages continued to range from slightly below to slightly above average rainfall totals for 2025 through the end of May (around 75 to 130 percent of average). The USGS’ Poamoho Rain Gage No. 1 had the highest year-to-date total of 87.32 inches, keeping them around 93 percent of their average for the year so far.

Maui County: [Maui May 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi May 2025 map] [year-to-date map]

The vast majority of rain gages across Maui County recorded below average rainfall totals for the month of May, with the driest areas being the leeward coast and central valley. Many of the sites in these areas received less than 10 percent of their May average rainfall, including the Kealia Pond RAWS and National Weather Service (NWS) Kihei 2 gages with zero rainfall for the month. The USGS’ rain gage atop Puʻu Kukui had the highest monthly total of 14.28 inches (51 percent of average), and the highest daily total of 2.56 inches on May 8. The West Wailuaiki Stream rain gage was a close second highest monthly total at 12.73 inches (68% of average). The NWS gage at Wailuku recorded its driest May since 2012 with 0.13 inches.

Rainfall totals for 2025 through the end of May were wide-ranging across Maui County, though the majority remained around 50 to 90 percent of their YTD averages. The USGS’ rain gage at Puʻu Kukui gage remains on top with the county’s highest year-to-date total of 85.32 inches (a meager 53 percent of their YTD average).

Island of Hawaiʻi: [May 2025 map] [year-to-date map]

The leeward side’s summer wet season  performed well again, where several sites along the Kona and Kaʻū district slopes between Kailua-Kona and Kahuku came in above average, including a few up to 2 to 3 times their May averages. The Kona International Airport recorded its 3rd wettest May on record with 2.00 inches. The opposite was seen for most other areas of the Big Island, with the driest spots in the Hāmākua and South Kohala districts and many gages struggling to reach 30 percent of their May averages. The Kawainui Stream (since 2010), Waimea Plain (since 2012), and Laupahoehoe (since 2010) rain gages in the Hāmākua district each posted their driest May (driest on record for Kawainui stream). The Glenwood gage in the Puna district recorded its driest May since 2006. The highest monthly total came from the NWS rain gage at Waiʻaha Stream with 11.70 inches (250 percent of average). This site also recorded the highest daily total for the month of 1.58 inches on May 18.

Rainfall totals for 2025 through the end of May were near to below average at most of the rain gages across most of the Big Island, except for the kona slopes which are still around 100 to 180 percent of their averages for the year so far. The USGS’ rain gage at Honoliʻi Stream had the highest year-to-date total of 39.23 inches (41 percent of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Hydrology Program Manager
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: April 2025

Prepared: May 8, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

April had a respectable showing state-wide to round out the 2024-2025 wet season. The majority of stations reported near to above average rainfall totals for the month, with most of that falling during the second half of the month. The month began with moderate southeast to south winds and a surface ridge over the state, ahead of a cold front approaching from the northwest. The front moved through Kauaʻi on the 3rd and stalled over the Kauaʻi Channel on the 4th before dissipating. Moderate to fresh east to northeast trade winds filled in behind the front and continued through around the 14th. An increase in low-level moisture around the 9th and 10th acted to boost trade wind showers with some pockets of moderate to heavy rain, especially on Kauaʻi and the Big Island, though no significant flood impacts occurred.

Around the middle of the month, the trade winds eased enough to allow a land/sea breeze pattern to set up from the 16th through the 19th. A disturbance aloft moving over the state during this time resulted in enough instability for some heavy showers and thunderstorms. The 17th focused the heaviest showers along Windward Maui and Oʻahu, as well as leeward Big Island and Kauaʻi. The 17th through 18th saw the heaviest rainfall with windward and interior portions of Kauaʻi and Oʻahu picking up 7 to 10 inches of rain in 24 hours, Mt. Waiʻaleʻale, where they picked up the highest daily total for that island this month. Kauaʻi Emergency Management reported flash flooding near the Hanalei River Bridge that day as well. The Poamoho Rain Gage #1 also recorded the highest daily total for Oʻahu in April. Other windward areas saw around 2 to 4 inches of rain, while the light winds and sea breezes allowed leeward areas to pick up several tenths of an inch of much needed rainfall.

Moderate to fresh easterly trades with typical scattered windward and mauka showers returned for the next few days as high pressure reasserted itself north of the area. During this period, a few heavier showers occurred over the leeward slopes of the Big Island and portions of Maui with rainfall rates of up to 2 inches per hour at times, though no significant flooding was observed. Trades weakened and shifted out of the southeast beginning on the 22nd ahead of the next weather maker in the form of a developing surface low and accompanying upper-level low northwest of the islands. These lows, along with the associated instability maximum and most thunderstorm activity, remained centered just west of Kauaʻi, with the remainder of the state under high-moisture south to southeast flow. Portions of Kauaʻi, Oʻahu, and Maui saw some heavy showers stream over them from the south with rainfall rates of around one inch per hour over the next couple of days, but the moderate to fresh wind speeds kept the showers moving quickly enough to avoid any significant flooding effects.

As the lows to the northwest weakened and stalled west of Kauaʻi into the weekend of the 25th and 26th, the moderate southeasterly winds weakened, allowing land and sea breezes to set up over the majority of the state. However, Hawaiʻi remained under a moist and relatively unstable airmass for the next few days, allowing some afternoon showers to become somewhat heavy over interior and leeward areas of Kauaʻi and Oʻahu. None of these were enough for any real flooding impacts. Trade winds began to slowly return to round out the month as the troughs to the west dissipated.

Island of Kauaʻi : [April 2025 map] [year-to-date map]

April rainfall totals were overwhelmingly above average across Kauaʻi, with only a few exceptions along the southern coast of the island, which were between 60-90 percent of average. The remaining sites ranged from just above average to several in the range of 3 to 6 times their April averages. The U.S. Geological Survey’s (USGS) gage on Mount Waiʻaleʻale had the highest monthly total of 47.12 inches (125 percent of average), and the highest daily total of 8.48 inches on April 18. This site’s monthly total was also the highest monthly total across the entire state for April. The Kilohana rain gage came in second place for the month with 27.78 inches (126 percent of average).

Most of the gages on Kauaʻi ranged from slightly below to slightly above average rainfall totals for 2025 through the end of April (around 85 to 150 percent of average). Dry conditions on the south side of the island kept sites like Port Allen, Poʻipū, and ʻŌmaʻo only around 25 to 50 percent of average for the year so far. The Mount Waiʻaleʻale rain gage had the highest year-to-date total again this month with 92.91 inches, which was 74 percent of average.

Island of Oʻahu: [April 2025 map] [year-to-date map]

The majority of the Oʻahu rain gages posted near to above average totals for the month of April. Gages along the Waiʻanae and Koʻolau Ranges had the highest totals, ranging from around 5 to 12 inches and some sites up to 2 or 3 times their April averages. The USGS’ Poamoho Rain Gage No. 1 had the highest monthly total of 26.48 inches (121 percent of average), and the highest daily total of 8.92 inches on April 17. The Honouliuli rain gage near West Loch logged its lowest April total on record of 0.02 inches, which is only 2 percent of their monthly average.

Most of the gages on Oʻahu ranged from slightly below to slightly above average rainfall totals for 2025 through the end of April (around 75 to 130 percent of average). A good April showing allowed many sites to recover some of the deficit from the first few months of the year. The USGS’ Poamoho Rain Gage No. 1 had the highest year-to-date total of 72.45 inches, bringing them up to 94 percent of their average for the year so far.

Maui County: [Maui April 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi April 2025 map] [year-to-date map]

Rain gages across the windward and mauka areas of Maui County had mostly near to above average rainfall totals for the month of April, with the notable exceptions of West Wailuaiki Stream and the Hana Airport only bringing in around half of their average amounts this month. Most leeward Maui gages had totals at around 30 to 60 percent of the April average, which wasn’t much help to the already severe drought in those areas. The USGS’ rain gage atop Puʻu Kukui had the highest monthly total of 22.34 inches (58 percent of average), and the highest daily total of 2.84 inches on April 10.

Rainfall totals for 2025 through the end of April were near to below average at most of the gages across Maui County. Underwhelming April totals on the windward coast of Maui allowed the USGS’ rain gage at Puʻu Kukui to surpass the West Wailuaiki Stream gage for the highest year-to-date total with 71.04 inches (53 percent of average).

Island of Hawaiʻi: [April 2025 map] [year-to-date map]

We are already starting to see the shift toward the leeward side’s summer wet season, where several sites along the kona and Kaʻū slopes came in well above their April averages. The opposite was seen along the windward side with many gages struggling to reach 30 percent of their April averages. In the North Hilo District, the Laupahoehoe rain gage posted its lowest April total on record of 0.99 inches, a paltry 6% of its April average. The highest monthly total came from the NWS’ rain gage at Waiaha Stream with 8.70 inches (217 percent of average). This site also recorded the highest daily total for the month of 1.69 inches on April 16.

Rainfall totals for 2025 through the end of April were near to below average at most of the rain gages across most of the Big Island, except for the kona slopes which received up to 150 percent of their averages for the year so far. The USGS’ rain gage at Honoliʻi Stream had the highest year-to-date total of 32.23 inches (41 percent of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Tina Stall
Hydrology Program Manager
NOAA/NWS Weather Forecast Office Honolulu

Monthly Precipitation Summary

State of Hawaii

Month: March 2025

Prepared: April 7, 2025

Note:  This summary uses the arithmetic mean, or average, for “normal” rainfall values.

Averages used in this summary have switched to the 1991-2020 values where available.

State: [Text data table for rain gages]

March is normally one of the wettest months of the year, especially for the windward slopes of the state. It was not a normal March in 2025. The month started with light winds due to a high pressure ridge over the state.  Trade winds developed on March 2 as the ridge shifted northward and continued through the next two weeks. Trade wind intensities increased to fresh to strong levels on March 4 and remained at these levels through March 13. A low pressure system aloft produced unstable conditions that helped enhance the trade wind rainfall on March 10, resulting in the wettest day of the month for several of the windward slopes across the state. Rainfall totals for the day were 2 to 5 inches over the windward slopes of Kauaʻi and Maui, and 3 to 6 inches over the windward slopes of the Big Island above Hilo and Honomū. Although it was a wet day, rain rates were insufficient to produce significant flooding problems.

The fresh to strong trades eased to moderate to fresh levels on March 14, then veered to an east-southeasterly direction on March 16 in response to a low pressure system several hundred miles northwest of Kauaʻi. This shift in low level wind direction, coupled with unstable conditions aloft, activated a local terrain interaction mechanism that greatly enhances rainfall along the windward slopes of the Koʻolau Range on Oʻahu. The persistent downpours generated flash flooding in several streams between Kāneʻohe and Hauʻula. Waikāne Stream overflowed onto Kamehameha Highway and closed both lanes. Three vehicles on the highway were stranded in knee deep floodwaters. Event totals along the Koʻolau Range were 3 to 7 inches.

Easterly trades resumed on March 19 at moderate to fresh intensities and persisted through March 21. On March 22, the surface pressure gradient weakened considerably, resulting in light to moderate east to east-southeast winds through March 26, then southeasterly to southerly winds from March 27 through the remainder of the month. Atmospheric conditions were rather stable during this period, so rainfall totals, if they occurred at all, were not significant.

Island of Kauaʻi : [March 2025 map] [year-to-date map]

March rainfall totals were mostly below average across Kauaʻi. Locations along the lower leeward slopes from Hanapēpē to Waimea were especially dry with monthly totals at less than an inch and less than 20 percent of the long term March average. The U.S. Geological Survey’s (USGS) gage on Mount Waiʻaleʻale had the highest monthly total of 26.05 inches (69 percent of average), and the highest daily total of 4.57 inches on March 10. The Līhuʻe Airport and Wainiha gages reported their lowest March totals since 2008.

All of the gages on Kauaʻi had near to below average rainfall totals for 2025 through the end of March. Dry conditions on the northwest side of the island allowed the Mount Waiʻaleʻale rain gage to pass the USGS’ Kilohana rain gage for the highest year-to-date total. The Mount Waiʻaleʻale year-to-date total of 45.79 inches was 53 percent of average.

Island of Oʻahu: [March 2025 map] [year-to-date map]

Nearly all of the Oʻahu rain gages posted near to below average totals for the month of March. Gages along the lower leeward slopes of the Waiʻanae Range and on the eastern tip of the island had monthly totals below 1 inch and less than 30 percent of average. The USGS’ Poamoho Rain Gage No. 1 had the highest monthly total of 25.43 inches (120 percent of average), and the highest daily total of 6.75 inches on March 16. The Kamehame rain gage logged its lowest March total since 2008.

Most of the gages on Oʻahu had near to below average rainfall totals for 2025 through the end of March. Two consecutive dry months have offset the wet conditions in late January. The USGS’  Poamoho Rain Gage No. 1 had the highest year-to-date total of 45.97 inches (83 percent of average).

Maui County: [Maui March 2025 map] [year-to-date map] [Molokaʻi/Lanaʻi March 2025 map] [year-to-date map]

Rain gages across Maui County had mostly below average rainfall totals for the month of March. Several leeward Maui gages had totals at less than 10 percent of the March average. The USGS’ rain gage on top of Puʻu Kukui had the highest monthly total of 17.97 inches (47 percent of average), and the highest daily total of 5.04 inches on March 10. The Pukalani gage reported its lowest March total on record. The Kahakuloa, Māhinahina, and Waikapū Country Club had their lowest March totals since 2008.

Rainfall totals for 2025 through the end of March were near to below average at most of the gages across Maui County. The USGS’ rain gage at West Wailuaiki Stream had the highest year-to-date total of 50.58 inches (79 percent of average).

Island of Hawaiʻi: [March 2025 map] [year-to-date map]

Most of the Big Island rain gages recorded below average rainfall totals for the month of March. The highest monthly total from the automated sites came from the USGS’ rain gage at Honoliʻi Stream with 17.37 inches (70 percent of average). The highest overall total came from the manually observed CoCoRaHS network gage at Wainaku near Hilo. This site reported 17.43 inches for the month. The highest daily was 6.52 inches on March 10 from the Honoliʻi Stream rain gage. In the Kaʻū District, the Pali 2 rain gage posted its lowest March total since 2010.

Rainfall totals for 2025 through the end of March were near to below average at most of the rain gages across the Big Island. The USGS’ rain gage at Honoliʻi Stream had the highest year-to-date total of 28.48 inches (51 percent of average).

Data Sources: Data used in this report are from National Weather Service sources including climate network weather observation stations at Līhuʻe, Honolulu, Kahului, and Hilo, the Ua Net network of automated rain gages, and selected Cooperative Observer sites.  Additional data come from automated rain gages operated by the State of Hawaiʻi Department of Land and Natural Resources, the U.S. Geological Survey, the U.S. Bureau of Land Management, the U.S. National Park Service, the Department of Defense, the U.S. Fish and Wildlife Service, and the U.S. Department of Agriculture, as well as manual observations from the Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS).  Averages come from the National Centers for Environmental Information (1991-2020 series) and the Rainfall Atlas of Hawaiʻi (https://www.hawaii.edu/climate-data-portal/hawaii-climate-atlases/). Supplemental data used in some of the analyses are from the Hawaiʻi Climate Data Portal (https://www.hawaii.edu/climate-data-portal/).  Data presented here are not certified and should be used for informational purposes only.

Kevin R. Kodama
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu