Summer May Be Just Getting Started
By Gary McManus
Climatologist
The Oklahoma Climatological Survey
7/25/2006

NORMAN - Oklahoma's latest heat wave may seem like one of the worst in recent memory, but that's possibly due to the fact that, well...it's the most recent in memory. That's not to say it hasn't been a dreadful little heat wave thus far. Coupled with a nearly year-long drought and a lot of summer still remaining, the potential is there for it to become even more memorable.

Part of the problem is that Oklahoma has taken several of the last few summers off, so perhaps it has gotten a bit spoiled. Oklahoma City failed to reach 100 degrees in 2002 and 2004, and only hit that mark twice in 2005. Statewide, the summer of 2004 was the 4th coolest on record, while 2005's was slightly below normal. The highest temperature of the previous two years was 106 degrees, recorded last July at both Claremore and Grandfield. There were plenty of 100-degree temperatures reported at other locations across the state during those two summers - 805 reports from the Oklahoma Mesonet's more than 115 stations - but that pales in comparison to the 1130 that have occurred this year (through July 24).

Will Rogers Airport in Oklahoma City has already recorded 100-degree temperatures 12 times. The Oklahoma Mesonet site at Grandfield has topped the century mark 25 times, with Tipton right behind at 23. Alva, Buffalo, Cherokee, Fairview, Freedom, and Walters have all hit 109 degrees to tie for the state's highest recorded temperature this summer. Those readings all occurred between July 17-21, the height of the heat wave.

And while 1980 remains the standard for triple-digit days across much of Oklahoma, several recent years have also had their share of sweltering heat. The summers of 1998 through 2001 were all above normal, with 1998 ranking as the 8th warmest in state history. The Oklahoma Mesonet had well over 4000 reports of triple-digit temperatures during 1998, topped by the 112 degrees reported at both Mangum and Hollis on June 20 of that year. Oklahoma City was at or above the 100-degree mark 40 times, nearing the hallowed 1980 benchmark of 50.

The bad news, as related to this year, is the timing of these past heat waves. Only 15 of the 40 instances Oklahoma City reached 100 degrees during 1998 occurred prior to July 24. Even worse, of the 32 triple-digit temperatures in 2000, only one fell before the 24th. In fact, of the 1141 times Oklahoma City has reached 100 degrees from 1896-2005, only 399 (35 percent) occurred before July 24 each year. The numbers are similar for Tulsa, where only 242 of the 723 triple-digit readings since 1938 have come before the 24th. The Climate Prediction Center's latest three-month outlook for August-October indicates an increased probability of above normal temperatures. In other words, the dog days of summer may have just started barking.