By Mark Shafer, Director of Climate Information and Gary McManus, Climatologist
Oklahoma Climatological Survey


NORMAN - On Thursday, June 7, Oklahoma City's Will Rogers World Airport hit 90 degrees for the first time this year. Although not the latest on record, it is rather unusual to go so far into the year without turning up the heat. Only 19 other years, out of 110 years that Oklahoma City has temperature data, went as late as June 7 before striking 90 degrees. The latest was in 1899, which went until July 5. The earliest 90-degree day on record was February 1 in 1911, when the mercury just barely touched 90 degrees.

A late start to the season does not necessarily mean an early end or an easy summer. Late starts trim about 10 days off the total, on average, but some years such as 1978 have registered as many as 94 days of 90 or above, including 35 days over 100 degrees. The long-term average is 69 days. But who can forget the beautiful, cool summer of 1906, which had only 19 90-degree days? The summers of 1979, 1978, 1932, and even 1899 started late but went well into October with temperatures above 90.

May Climate Summary Released
May was dominated by turbulent weather generated by several powerful upper-level storm systems. Severe thunderstorms and their by-products - including tornadoes, large hail and widespread flash- and river-flooding - were common throughout the month. The heavy rainfall certainly eradicated any remnants of the droughty conditions of the previous two years. The month ranked as the 24th wettest since 1895, well over an inch above normal. The statewide average temperature was above normal as well, and the month finished as the 41st warmest May on record. The most tempestuous weather occurred between May 4-9 as a large upper-level storm sat over the Desert Southwest for nearly a week, ejecting smaller impulses over the state. Those impulses helped to generate at least 15 tornadoes during this period, including an EF3 twister that struck the town of Sweetwater on May 5. Despite the tornadoes, flooding was the dominant severe threat during May. Thirty-five flash flood warnings were issued by the NWS during the month, the majority of which occurred between May 7-9. Extreme events during the month included a report of softball size hail from Harper County on the 23rd and 6.81 inches of rainfall recorded by the Lane Mesonet site on the 7th.


Media Contact:

Cerry Leffler
Oklahoma Climatological Survey
120 David L. Boren Blvd., Suite 2900
Norman, OK 73072-7305
405-325-2541
405-325-2550 (fax)
cerry@ou.edu

For Additional Information:

Mark Shafer
Director of Climate Information
120 David L. Boren Blvd., Suite 2900
Norman, OK 73072-7305
405-325-2541
405-325-2550 (fax)
mshafer@ou.edu