Extreme Heat Warning

URGENT - WEATHER MESSAGE
National Weather Service Las Vegas NV
112 PM PDT Tue Jul 21 2026

AZZ002-570-571-576-CAZ522>527-NVZ016-017-020-022-025-026-221200-
/O.UPG.KVEF.XH.A.0002.260723T1700Z-260728T0300Z/
/O.NEW.KVEF.XH.W.0002.260723T1700Z-260728T0300Z/
Lake Havasu and Fort Mohave-Lake Mead - AZ side-Lake Mohave - AZ
side-Northwest Deserts-Death Valley National Park-Western Mojave
Desert-Eastern Mojave Desert-Morongo Basin-Cadiz Basin-San
Bernardino County-Upper Colorado River Valley-Northeast Clark
County-Western Clark and Southern Nye County-Las Vegas Valley-
Southern Clark County-Lake Mead - NV side-Lake Mohave - NV side-
Including the cities of Stovepipe Wells, Moapa, Desert Rock,
Henderson, Mesquite, Amargosa Valley, Golden Valley, Bullhead City,
Dolan Springs, South Cove, Desert Hills, North Las Vegas, Mountain
Pass, Pahrump, Yucca Valley, Twentynine Palms, Boulder City, Mitchell
Caverns, Las Vegas, Indian Springs, Hoover Dam, Lake Havasu City,
Primm, Searchlight, Shoshone, Daggett, Valentine, Wikieup, Barstow,
Fort Irwin, Vidal Junction, Needles, Baker, Overton, Yucca, Laughlin,
Kingman, Temple Bar, Furnace
Creek, Topock, Cal-Nev-Ari, and Morongo Valley
112 PM PDT Tue Jul 21 2026 /112 PM MST Tue Jul 21 2026/

...EXTREME HEAT WARNING IN EFFECT FROM 10 AM PDT /10 AM MST/ THURSDAY
TO 8 PM PDT /8 PM MST/ MONDAY...

* WHAT...Dangerously hot conditions expected. Afternoon temperatures
  in the desert valleys will climb into the 108 to 114 degree range,
  and may exceed 115 along the Colorado River Valley and 120 in Death
  Valley. Overnight lows generally 80 to 95 degrees.

* WHERE...Portions of northwest Arizona, southeast California, and
  southern Nevada including the Greater Mojave Desert region.

* WHEN...From 10 AM PDT / MST Thursday to 8 PM PDT / MST Monday.

* IMPACTS...Heat related illnesses increase significantly during
  extreme heat events.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors.

Do not leave young children and pets in unattended vehicles. Car
interiors will reach lethal temperatures in a matter of minutes.

Take extra precautions when outside. Wear lightweight and loose
fitting clothing. Try to limit strenuous activities to early morning
or evening. Take action when you see symptoms of heat exhaustion and
heat stroke.

To reduce risk during outdoor work, the Occupational Safety and
Health Administration recommends scheduling frequent rest breaks in
shaded or air conditioned environments. Anyone overcome by heat
should be moved to a cool and shaded location. Heat stroke is an
emergency! Call 9 1 1.

Monitor the latest forecasts and warnings for updates.

&&

$$

MW

URGENT - WEATHER MESSAGE
National Weather Service Los Angeles/Oxnard CA
1233 PM PDT Tue Jul 21 2026

CAZ383-220745-
/O.CON.KLOX.XH.W.0003.260723T1700Z-260728T0300Z/
Antelope Valley-
Including the cities of Palmdale, Lake Los Angeles, and Lancaster
1233 PM PDT Tue Jul 21 2026

...EXTREME HEAT WARNING REMAINS IN EFFECT FROM 10 AM THURSDAY TO 8
PM PDT MONDAY...

* WHAT...Hot daytime conditions with high temperatures between 100
  and 108 common. Warm overnight conditions will bring less relief
  than usual.

* WHERE...Antelope Valley.

* WHEN...From 10 AM Thursday to 8 PM PDT Monday.

* IMPACTS...There is a high risk for dangerous heat illness,
  especially for sensitive groups like the very young, the very old,
  those without air conditioning, and those active outdoors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors. Do not leave young
children and pets in unattended vehicles. Limit strenuous activities
to early morning or evening. Take action when you see symptoms of
heat exhaustion and heat stroke.

&&

$$

URGENT - WEATHER MESSAGE
National Weather Service San Diego CA
1023 AM PDT Tue Jul 21 2026

CAZ060-220515-
/O.UPG.KSGX.XH.A.0005.260722T1700Z-260728T0300Z/
/O.NEW.KSGX.XH.W.0006.260723T1700Z-260728T0300Z/
Apple and Lucerne Valleys-
Including the cities of Hesperia, Apple Valley, Lucerne Valley,
and Victorville
1023 AM PDT Tue Jul 21 2026

...EXTREME HEAT WARNING IN EFFECT FROM 10 AM THURSDAY TO 8 PM PDT
MONDAY...

* WHAT...Dangerously hot conditions with high temperatures 100 to
  108 and low temperatures in the 70s and lower 80s.

* WHERE...Apple and Lucerne Valleys.

* WHEN...From 10 AM Thursday to 8 PM PDT Monday.

* IMPACTS...Heat related illnesses increase significantly during
  extreme heat events.

* ADDITIONAL DETAILS...Areas of major HeatRisk. Elevated low
  temperatures will limit overnight relief from the heat.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors.

&&

$$

Heat Advisory

URGENT - WEATHER MESSAGE
National Weather Service Los Angeles/Oxnard CA
1233 PM PDT Tue Jul 21 2026

CAZ038-088-342>345-348-352-353-356>358-369>382-548-220745-
/O.CON.KLOX.HT.Y.0010.260722T1700Z-260728T0300Z/
Cuyama Valley-Santa Clarita Valley-Santa Lucia Mountains-Southern
Salinas Valley-San Luis Obispo County Interior Valleys-San Luis
Obispo County Mountains-Santa Ynez Valley-Santa Ynez Mountains
Eastern Range-Santa Barbara County Interior Mountains-Lake
Casitas-Ojai Valley-Central Ventura County Valleys-Western Santa
Monica Mountains Recreational Area-Eastern Santa Monica Mountains
Recreational Area-Calabasas and Agoura Hills-Western San Fernando
Valley-Eastern San Fernando Valley-Southeastern Ventura County
Valleys-Santa Susana Mountains-Southern Ventura County Mountains-
Northern Ventura County Mountains-Interstate 5 Corridor-Western
San Gabriel Mountains and Highway 14 Corridor-Eastern San Gabriel
Mountains-Western Antelope Valley Foothills-Eastern Antelope
Valley Foothills-Los Angeles County San Gabriel Valley-
Including the cities of Mount Wilson, Creston, Ozena, Northridge,
La Canada Flintridge, Mount Pinos, Montecito Hills, Valencia,
Santa Clarita, Acton, Ojai, Lake Nacimiento, Lake Castaic,
Shandon, Oak View, San Rafael Mountain, Thousand Oaks, Mount
Baldy, Topanga, Fillmore, Universal City, East Los Angeles, Paso
Robles, Solvang, Woodland Hills, Pearblossom, Llano, Lake
Palmdale, Oat Mountain, San Miguel, San Gabriel, Meiners Oaks,
Elizabeth Lake, Newhall, Simi Valley, Rose Valley, Lockwood
Valley, Matilija, The Angeles Crest Highway, Atascadero, Santa
Paula, Templeton, Carrizo Plain, La Panza Range, Westlake
Village, Van Nuys, Topatopa Mountains, Wrightwood, Piru, New
Cuyama, Malibu Lake, Los Olivos, Figueroa Mountain, Hearst
Castle, Malibu Bowl, Newbury Park, Burbank, Tejon Pass, Lake
Cachuma, Warm Springs, Gorman, Valyermo, Moorpark, Big Pine
Mountain, Glendale, Mill Creek, Pasadena, Pomona, Irish Hills,
Santa Ynez, Chatsworth, El Monte, Caliente Range, Santa Margarita
Lake, Sunland, and Pyramid Lake
1233 PM PDT Tue Jul 21 2026

...HEAT ADVISORY REMAINS IN EFFECT FROM 10 AM WEDNESDAY TO 8 PM PDT
MONDAY...

* WHAT...Hot daytime conditions with high temperatures between 97
  and 107 common. Warm overnight conditions will bring less relief
  than usual.

* WHERE...Valleys and mountains of Los Angeles, Ventura, Santa
  Barbara, and San Luis Obispo Counties.

* WHEN...From 10 AM Wednesday to 8 PM PDT Monday.

* IMPACTS...There is a high risk for dangerous heat illness,
  especially for sensitive groups like the very young, the very old,
  those without air conditioning, and those active outdoors.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors. Do not leave young
children and pets in unattended vehicles. Limit strenuous activities
to early morning or evening. Take action when you see symptoms of
heat exhaustion and heat stroke.

&&

$$

URGENT - WEATHER MESSAGE
National Weather Service San Francisco CA
1017 AM PDT Tue Jul 21 2026

CAZ502-504-506-508-510-512>518-220400-
/O.NEW.KMTR.HT.Y.0009.260721T1717Z-260722T0400Z/
Marin Coastal Range-North Bay Interior Mountains-North Bay
Interior Valleys-San Francisco Bay Shoreline-East Bay Interior
Valleys-Santa Cruz Mountains-Santa Clara Valley Including San
Jose-Eastern Santa Clara Hills-East Bay Hills-Southern Salinas
Valley/Arroyo Seco and Lake San Antonio-Santa Lucia Mountains and
Los Padres National Forest-Mountains of San Benito County And
Interior Monterey County including Pinnacles National Park-
1017 AM PDT Tue Jul 21 2026

...HEAT ADVISORY IN EFFECT UNTIL 9 PM PDT THIS EVENING...

* WHAT...Temperatures into the mid 90 and low 100s.

* WHERE...Entire Bay Area excluding the immediate Pacific Coast zones
  and San Francisco. Also, including Interior Central Coast.

* WHEN...Until 9 PM PDT this evening.

* IMPACTS...This level of heat affects most individuals sensitive to
  heat, especially those without effective cooling and/or adequate
  hydration. Impacts possible in some health systems and in
  heat-sensitive industries.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Hydration is a critical piece to surviving the heat. Drink water, and
if possible, take water to those who are vulnerable.

Beat the heat and check the backseat! Do not leave young children or
pets in unattended vehicles.Car interiors will reach lethal
temperatures in a matter of minutes.

To reduce risk during outdoor work, the Occupational Safety and
Health Administration recommends scheduling frequent rest breaks in
shaded or air conditioned environments. Anyone overcome by heat
should be moved to a cool and shaded location. Heat stroke is an
emergency! Call 9 1 1.

&&

$$

BFG

Small Craft Advisory

URGENT - MARINE WEATHER MESSAGE
National Weather Service San Francisco Bay Area
232 PM PDT Tue Jul 21 2026

PZZ565-220545-
/O.NEW.KMTR.SC.Y.0082.260723T0400Z-260724T0400Z/
Coastal Waters from Point Pinos to Point Piedras Blancas
California out to 10 NM-
232 PM PDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY IN EFFECT FROM 9 PM WEDNESDAY TO 9 PM PDT
THURSDAY...

* WHAT...Northwest winds 15 to 25 kt with gusts up to 30 kt
  expected.

* WHERE...Coastal Waters from Point Pinos to Point Piedras
  Blancas California out to 10 NM.

* WHEN...From 9 PM Wednesday to 9 PM PDT Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

For more information from the National Weather Service visit
http://weather.gov/sanfrancisco

URGENT - MARINE WEATHER MESSAGE
National Weather Service Los Angeles/Oxnard CA
1253 PM PDT Tue Jul 21 2026

PZZ673-676-220400-
/O.CON.KLOX.SC.Y.0105.260721T2100Z-260723T1000Z/
Waters from Pt. Sal to Santa Cruz Island CA and westward 60 nm
including San Miguel and Santa Rosa Islands-
Outer waters from Santa Cruz Island to San Clemente Island to
60 NM offshore including San Nicolas and Santa Barbara Islands-
1253 PM PDT Tue Jul 21 2026

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 3 AM PDT
THURSDAY...

* WHAT...Hazardous sea conditions.

* WHERE...Waters from Pt. Sal to Santa Cruz Island CA and
  westward 60 nm including San Miguel and Santa Rosa Islands and
  Outer waters from Santa Cruz Island to San Clemente Island to
  60 NM offshore including San Nicolas and Santa Barbara Islands.

* WHEN...Until 3 AM PDT Thursday.

* IMPACTS...Conditions will be hazardous to small craft.

* ADDITIONAL DETAILS...See the Coastal Waters Forecast (CWFLOX)
  for more.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Flood Watch

Flood Watch
National Weather Service Reno NV
340 PM PDT Tue Jul 21 2026

CAZ072-073-NVZ001>003-220600-
/O.CON.KREV.FA.A.0003.000000T0000Z-260722T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greater Lake Tahoe Area-Mono County-Mineral and Southern Lyon
Counties-Greater Lake Tahoe Area-Greater Reno-Carson City-Minden
Area-
Including the cities of Mammoth Lakes, Stateline, Yerington, Lee
Vining, Markleeville, Hawthorne, Virginia City, Sparks, Schurz,
Bridgeport, Glenbrook, Gardnerville, Truckee, South Lake Tahoe,
Coleville, Smith Valley, Incline Village, Mina, Verdi, and Tahoe
City
340 PM PDT Tue Jul 21 2026

...FLOOD WATCH REMAINS IN EFFECT UNTIL 11 PM PDT THIS EVENING...

* WHAT...Flash flooding caused by excessive rainfall is possible due
  to thunderstorms.

* WHERE...Portions of east central California, including the
  following areas, Greater Lake Tahoe Area and Mono County and
  western Nevada, including the following areas, Greater Lake Tahoe
  Area, Greater Reno-Carson City-Minden Area and Mineral and
  Southern Lyon Counties.

* WHEN...Until 11 PM PDT this evening.

* IMPACTS...Excessive runoff may result in flooding of creeks,
  streams, urban areas, burn scars, and areas near steep terrain.

* ADDITIONAL DETAILS...
  - Deeper monsoonal moisture combined with daytime heating will
    produce scattered thunderstorms this afternoon and evening.
    Slower moving storms could redevelop over similar areas,
    increasing the risk for heavy rainfall capable of producing
    flash flooding.
  - http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

CJ

Extreme Heat Watch

URGENT - WEATHER MESSAGE
National Weather Service Hanford CA
632 PM PDT Tue Jul 21 2026

CAZ337-339-221000-
/O.CON.KHNX.XH.A.0001.260723T1500Z-260728T0400Z/
Indian Wells Valley-Mojave Desert-
Including the cities of California City, Inyokern, Ridgecrest,
Randsburg, Edwards AFB, and Rosamond
632 PM PDT Tue Jul 21 2026

...EXTREME HEAT WATCH REMAINS IN EFFECT FROM THURSDAY MORNING THROUGH
MONDAY EVENING...

* WHAT...Dangerously hot conditions with high temperatures between
  108 to 112 degrees.

* WHERE...Indian Wells Valley and Mojave Desert.

* WHEN...From Thursday morning through Monday evening.

* IMPACTS...Heat related illnesses increase significantly during
  extreme heat events.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors.

Do not leave young children and pets in unattended vehicles. Car
interiors will reach lethal temperatures in a matter of minutes.

&&

$$

EW