July 2019 Climate and Hydrology Summary

Tulsa: July 2019 was the 43rd coldest (81.7°F, tied 1997; since 1905) and the 45th wettest (4.05"; since 1888) July on record.

Fort Smith: July 2019 was the 59th coldest (81.7°F; since 1882) and the 46th wettest (3.33", tied 1984; since 1882) July on record.

Fayetteville: July 2019 was the 17th coldest (76.4°F, tied 2000; since 1950) and the 31st wettest (3.07"; since 1950) July on record.

Using the radar-derived estimated observed precipitation from the RFCs, rainfall totals for July 2019 ranged from around 0.50” to near 8” across eastern OK and northwest AR. A large portion of the HSA received 1”-3” of rain this month. These rainfall totals correspond to 25%-90% of the normal July rainfall for most of eastern OK and western AR, with some locations receiving as little as 10%-25% and others receiving 125%-250% of the normal July rainfall.

After an extremely wet May and June, July 2019 ended up with below normal rainfall for most of eastern OK and northwest AR. Some minor rises occurred along area rivers this month. Overall, temperatures were near normal for the month.

Showers and thunderstorms moved across east central OK, northwest AR, and west central AR through the morning hours of the 2nd, as an upper-level disturbance lifted north across the area. This activity brought 0.10” to around 1.5” of rain, with 1.5” to around 2” in southern Sequoyah and northern Le Flore Counties. This localized rainfall resulted in the Arkansas River at Van Buren and at Ozark to rise a little above flood stage. Later in the day, showers and thunderstorms developed over north central OK and south central KS near a weak cold front that was slowly sagging south. These storms congealed into a small complex, which began to impact northeast OK just before midnight. Storms slowly moved east along the OK/KS state line, bringing heavy rain of 1.5”-4” to primarily Osage and Washington Counties (as well as the adjacent counties just north of the state line in KS) through the early morning hours of the 3rd. Soon after sunrise, the storms moved further south, affecting locations north of I-44 in northeast OK. Additional redevelopment occurred in north central OK during the mid-morning hours near, which then moved into Osage County by noon. This activity continued through the afternoon and early evening hours, impacting locations along and northwest of the I-44 corridor. Rainfall totals were 0.25” to around 2.5”. Rises occurred along the Caney River, but flood stage was not exceeded.

A line of showers and thunderstorms moved south out of southeast KS and southwest MO into northeast OK and northwest AR during the afternoon of the 5th. These storms weakened, but additional development occurred along it’s outflow boundary, primarily over the Arkansas River valley from Tulsa, OK to Ozark, AR. This activity didn’t last long, weakening during the evening with the loss of daytime heating. Most of the affected area received 0.25” to around 1” of rain, but small pockets of 1.5”-2” occurred.

Scattered showers and thunderstorms developed during the afternoon of the 6th as a gust front from a decaying mesoscale convective system (MCS) moved into a moist and unstable airmass. These storms produced locally heavy rain and continued through the evening before dissipating with the loss of daytime heating. However, some convection continued just north of the OK/KS line in southeast KS through midnight. Rainfall totals ranged from around 0.10” to around 3”. This rain impacted the Neosho River, causing the river to rise to near, but just below, flood stage near Commerce.

A series of weak disturbances moved across the region on the periphery of an upper-level ridge on the 7th-8th, bringing scattered showers and thunderstorms to parts of eastern OK and northwest AR. The heaviest rainfall occurred shortly after midnight on the 8th in southeast OK, primarily affecting Pittsburg County, due to a slow-moving cluster of storms near a weak boundary. Rainfall in this area was 1”-4” before the storms dissipated around sunrise. Scattered showers and thunderstorms redeveloped over eastern OK and northwest AR through the day as a weak upper-level wave moved east across the region. In typical summer fashion, this activity dissipated at sunset. Rainfall totals were generally around 0.10” to around 1”, though Pittsburg County and other more localized areas received 1.5”-3” of rain.

A line of showers and thunderstorms moved south out of southeast KS and into northeast OK during the late morning of the 10th. These storms continued to sweep south across much of eastern OK and western AR before exiting the area by mid-evening. Rainfall totals were 0.10” to around 1”, with some pockets of 1”-1.5”.

During the late evening of the 21st, a line of storms developed over southeast KS along a cold front, which moved south into northeast OK. The cold front and storms then moved southeast through the overnight hours, bringing rain to locations near and north of I-40. The rain came to an end shortly after sunrise on the 22nd. Rainfall totals ranged from around 0.25” to 3”.

Scattered showers and thunderstorms moved south out of KS and into northeast OK just after midnight on the 29th, ahead of cold front. This activity continued to move southeast across eastern OK and northwest AR through the morning and afternoon hours as the boundary sagged south. An isolated thunderstorm affected locations near I-44 in the evening. Rainfall totals were generally a few hundredths of an inch to around 1”, with locally higher amounts of 1”-2”.

According to the Drought Monitor from July 30, 2019, no drought or abnormally dry conditions were present across eastern OK and northwest AR.