monthly climate summary

June followed its normal script almost to the letter with a rainy and stormy first half of the month that gave way to the beginnings of a long hot stretch of Oklahoma summer. Mother Nature did manage to throw in a nice improvisation at the end of the month with a cool front dropping temperatures into the 80s over much of the state. The previous heat was enough to end the state's streak of below normal months at four, however.

In a state so accustomed to highly variable and often tumultuous weather, May 2013 will be long remembered as one of its most notorious. The month began with some of the coldest late-spring weather in the state's history and finished with a flourish of violent weather, including one of Oklahoma's worst tornado disasters on record. Stirring the echoes of May 3, 1999, for many central Oklahoma residents, a massive and violent tornado churned its path of destruction from near Newcastle through south Oklahoma City and Moore before dissipating near Stanley Draper Lake.

The wet conditions of February failed to translate into March, but the cooler than normal weather continued virtually uninterrupted. According to data from the Oklahoma Mesonet, the month's statewide average temperature was 47.7 degrees, 2.5 degrees below normal and the 45th coolest March since records began in 1895. The two months together accomplished a relatively rare feat of late, becoming first consecutive months to finish below normal in Oklahoma since January and February 2011.

Winter roared back into Oklahoma during February, providing significant drought relief to much of the state while dumping as much as three feet of snow in the northwest. According to preliminary data from the Oklahoma Mesonet, the statewide average precipitation total for February was 3.03 inches, 1.27 inches above normal. That would rank the month as the 13th wettest February since records began in 1895, although melting snow in the northwest could push that mark higher. Radar estimates indicate 2-6 inches of liquid equivalent precipitation fell across the state during the month.

January seemed destined to finish on the dry side of normal, just as the eight months previous to it had, before a late-month burst of spring changed its fortunes. Tornado watches covered much of the eastern two-thirds of the state on the 29th, a by-product of the storm system that also dumped 1-3 inches of rain across parts of that same area. There were no confirmed tornadoes in Oklahoma, but reports of large hail and wind damage were scattered across the state.

A slide back to true wintry weather, the likes of which had not been seen across Oklahoma since early February 2011, was not enough to prevent the inevitable. Although the official numbers will not be released by the National Climatic Data Center (NCDC) for a few more days, it appears likely that 2012 will go down in the record books as Oklahoma’s warmest year on record. Those records date back to 1895. Preliminary data from the Oklahoma Mesonet indicate a statewide average temperature of 41.9 degrees for December.

Drought surged during November with a return to the dry, warm and windy weather pattern that Oklahoma has become accustomed to over the last couple of years. According to the latest U.S. Drought Monitor report, the amount of extreme to exceptional drought rose from 72 percent last week to 91 percent this week. The state had not seen that amount of extreme to exceptional drought since late September. Other than a small but persistent area of moderate drought in far northeastern Oklahoma, the entire state remained in at least severe drought according to the report.

It’s been awhile since Oklahoma has seen a month like October. Eleven months, to be exact. Not since September 2011 had Oklahoma seen a month where the statewide average temperature finished on the cold side of normal. In fact, 25 of the 30 months prior to October were warmer than normal, starting with April 2010. According to data from the Oklahoma Mesonet, October became the 26th coolest on record with a statewide average of 59.7 degrees, 1.6 degrees below normal.  Statewide records date back to 1895.

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.

According to data from the Oklahoma Mesonet, August finished one degree above normal to rank as the 53rd warmest on record and a half an inch below normal to come in as the 42nd driest. Those records date back to 1895. Despite those seemingly benign statistics, August actually had weather to suit just about all summer appetites. The month started with one of the hottest stretches the state has ever experienced, moved to mild and wet for a spell, then ended once again on the hot side.