February 2019 Climate and Hydrology Summary

Tulsa: February 2019 was the 47th coldest (39.9°F; since 1905) and the 54th driest (1.23", tied 2007, 1909; since 1888) February on record. A trace of snow fell, tying 18 other years (since 1900).

Tulsa: Daily records set or tied this month include a record warm mean temperature.

Fort Smith: February 2019 was the 38th warmest (46.0°F, tied 1986; since 1883) and the 21st wettest (5.05"; since 1883) February on record. A trace of snow fell, tying with 22 other years (since 1884).

Fort Smith: Records set or tied this month include a record warm maximum temperature.

Fayetteville: February 2019 was the 26th warmest (42.1°F; since 1950) and the 22nd wettest (3.26"; since 1950) February on record. A trace of snow fell, tying 14 other years (since 1950).

Using the radar-derived estimated observed precipitation from the RFCs, rainfall totals for February 2019 ranged from 0.5” to around 6” northwest to southeast across eastern OK and northwest AR. This corresponds to 110% to around 200% of the normal February rainfall in portions of east central and southeast OK and most of northwest AR, and 25% to 90% of normal for most of northeast OK and portions of southeast OK.

Most eastern OK and northwest AR received below normal rainfall this February, though portions of east central OK and west central AR were above normal. Winter weather this month included some light snow and some freezing rain.

Showers and isolated thunderstorms developed primarily over east central OK into northwest AR during the evening of the 5th and continued into the early morning hours of the 6th as warm air advection increased north of a warm front that was draped from south central OK to central AR. Most of the locations that saw this activity received around 0.75” or less of rain, but portions of Pittsburg, Haskell, and Sequoyah Counties received 1”-2” of rain.

On the 6th, a nearly stationary front bifurcated the area and resulted in a large temperature gradient from northeast OK/far northwest AR to southeast OK/west central AR. To the north was a shallow artic airmass, while south of the boundary was a warm, moist Gulf airmass. Showers and isolated thunderstorms in TX moved northeast into southeast OK during the morning of the 6th, and continued northeastward into northwest AR. This activity continued through the afternoon, with isolated showers and thunderstorms remaining over eastern OK and west central AR during the early evening hours. By mid-evening, a cluster of thunderstorms over north central OK moved east into northeast OK and far northwest AR. Another larger complex moved east from central OK into eastern OK around midnight. Showers and thunderstorms then affected eastern OK and western AR through most of the night, finally moving east of the area by sunrise on the 7th as the cold front finally pushed through with an upper-level system. With shallow cold air in place across northeast OK, some of this rain fell in sub-freezing surface temperatures, resulting in a glaze to 0.2” of ice accumulation. Rainfall totals for the numerous rounds of rain ranged from 0.25” to near 2.5”.

Scattered showers affected northwest AR through the morning of the 10th, and as warm air advection lifted northward during the day, additional showers developed from southeast OK through northwest AR. This activity then continued through most of the night, bringing around 0.25” to around 1.5” of rain. By sunrise on the 11th, scattered showers were impacting all of eastern OK and northwest AR. This activity became more widespread from east central OK to northwest AR as the morning progressed, coming to an end around noon. Additional scattered showers then developed during the afternoon hours, and by early evening, a large area of rain moved north out of TX into southeast OK within a broad warm conveyor belt ahead of a potent upper-level trough. This activity affected locations south of I-44 through much of the evening before moving east of the area. Meanwhile, scattered showers from north central OK moved into northeast OK and northwest AR during the late evening through overnight hours as the main upper-level system moved across the area. All of the precipitation finally came to an end in the pre-dawn hours of the 12th. Rainfall totals were around 0.25” to 1.25” for much of eastern OK and northwest AR. The 2-day combined rainfall total ranged from around 0.25” to 3”, resulting in minor flooding along the Poteau River near Panama.

Just before noon on the 19th, showers and isolated thunderstorms crossed the Red River out of TX and into southeast OK as an upper-level wave began to eject out of the desert southwest. This activity continued to spread north, affecting all of eastern OK and northwest AR during the afternoon. Near freezing temperatures combined with the wet-bulbing effect lead to snow and sleet across portions of northeast OK. Snow and sleet accumulations of 1”-2” were reported across western Osage and Pawnee Counties, with 0.25”—0.50” of sleet reported further east. While most of the rain had pushed northeast of the area by mid-evening, showers and isolated thunderstorms remained over southeast OK and northwest AR through the rest of the evening, finally shifting east of the area by midnight. Temperatures were sub-freezing in the higher elevations of northwest AR, allowing for some ice accumulation of 0.1”-0.25” on elevated surfaces. Rainfall totals were around 0.25” to around 1.5”.

Another shallow cold airmass slowed moved into the region on the 26th through 27th, bringing significantly colder temperatures to eastern OK and northwest AR. Temperatures were in the mid-50s to mid-60s across most of eastern OK and northwest AR the afternoon of the 26th, and near to below freezing by the afternoon of the 27th. This resulted in 24-hour temperatures differences of 25°F to 35°F. Freezing drizzle also accompanied this cold air, with ice accumulation on elevated surfaces. A thin glaze of ice also impacted roadways, especially bridges and overpasses, causing numerous accidents.

According to the Drought Monitor from February 26, 2019, no drought or abnormally dry conditions were present across eastern OK and northwest AR.

According to the Oklahoma Climatological Survey, the 30-day period January 30-February 28, 2019 was the 46th driest for northeast Oklahoma, the 35th wettest for east central Oklahoma, and the 34th wettest for southeast Oklahoma. Records go back to 1921. For the Year-to-Date period Jan. 1-Febraury 28, 2019, northeast Oklahoma ranked as the 14th wettest, east central Oklahoma was the 17th wettest, and southeast Oklahoma was the 38th wettest period.

Winter (Dec-Jan-Feb) 2018-19

Tulsa: Winter 2018-19 was the 55th coldest (39.7°F, tied 1945-46; since 1905-06) and the 11th wettest (8.65"; since 1888-89) Winter on record.

Fort Smith: Winter 2018-19 was the 30th warmest (43.5°F, tied 1940-41, 1907-08; since 1882-83) and the 5th wettest (14.50"; since 1882-83) Winter on record.

Fayetteville: Winter 2018-19 was the 23rd warmest (39.2°F; since 1949-50) and the 14th wettest (10.19"; since 1949-50) Winter on record.

According to the Oklahoma Climatological Survey, Winter 2018-19 (December 1, 2018-February 28, 2019) was the 6st wettest in northeast Oklahoma, east central Oklahoma ranked as the 7th wettest, and southeast Oklahoma was the 15th wettest period. Records go back to 1921.