Oklahoma monthly climate summary, 09/2012

              Copyright © 2012 Board of Regents of the University of Oklahoma.
Oklahoma Monthly Climate Summary 1
Hopes for drought relief were starting to fade as September wound down, only to be saved by a slow-moving soaker of a storm system during the month’s last week. The storm system’s prodigious moisture output was aided by a stationary front and in part by the remnants of Hurricane Miriam, spawned in the Pacific Ocean during the previous week. Totals of 2-4 inches were widespread across central and southern Oklahoma according to the Oklahoma Mesonet, mainly south of Interstate 40. The Mesonet site at Byars in Garvin County recorded 6.02 inches during the event. Unfortunately, not everybody shared in the drought-relieving moisture. Totals of less than an inch were common across the northern third of the state. Despite the attempted recovery at the end, September still finished nearly an inch below normal with a statewide average of 2.9 inches according to data from the Oklahoma Mesonet. The Mesonet site at May Ranch in Woods County had the lowest total with 0.74 inches during September while Byars in Garvin County led the state with 7.5 inches. When compared to normal, much of eastern and northern Oklahoma had deficits of 1-3 inches during September. The statewide average deficit for May-September climbed to more than 8 inches and ranked as one of the five driest such stretches on record, dating back to 1895.
SEPTEMBER 2012
Oklahoma Monthly Climate Summary
September 2012 Statewide Extremes
Description
Extreme
Station
Day
High Temperature
109ºF
Blackwell
7
Low Temperature
37ºF
Boise City, Kenton
15, 16
High Precipitation
7.46 in.
Byars
--
Low Precipitation
0.74 in.
May Ranch
--
September 2012 Statewide Statistics
Temperature
Average
Depart.
Rank (1895-2012)
Month (September)
74.1ºF
1.7ºF
36th Warmest
Year-to-Date (Jan-Sept)
67.0ºF
4.1ºF
1st Warmest
Precipitation
Average
Depart.
Rank (1895-2012)
Month (September)
2.92 in.
-0.89 in.
56th Driest
Year-to-Date (Jan-Sept)
23.63 in.
-4.84 in.
33rd Driest
Depart. = departure from 30-year normal
September ended with more than 42 percent of the state covered by exceptional drought in the latest U.S. Drought Monitor map. Exceptional drought is the worst such designation possible. More than 95 percent of Oklahoma was in the worst two drought categories, extreme and exceptional, and 100 percent remained in severe-to-exceptional drought.
The month was also on the warm side with an average temperature of 74.1 degrees, 1.7 degrees above normal. That ranks as the 36th warmest September on record. The highest temperature of the month, 111 degrees, came from the National Weather Service (NWS) site at Ralston on Sept. 4 and the lowest reading was a frigid 37 degrees recorded at Boise City and Kenton on Sept. 15 and 16, respectively. Oklahoma remains on course for its warmest year on record with a January-September statewide average temperature of 66.9 degrees, 4 degrees above normal. That bests the previous record of 66.3 degrees for the first nine months of the year from 1954 and keeps that year’s record annual mark of 62.8 degrees within reach. September became the 25th month out of the last 30 to finish warmer than normal, a streak that began with April 2010.
Severe weather was a bit more widespread during September after a benign August, although tornadoes remained absent. According to preliminary data from the NWS, no tornadoes have touched down in Oklahoma since June 1. That’s a record low total matched only by a similar June-September shutout in 2003. Accurate tornado statistics data back to 1950. Several instances of wind gusting to over 70 mph were reported during the month, including an 80 mph gust near Crowder on Sept. 26.