From January 26-27, 2009, a winter storm impacted parts of western North Texas, and western and central Oklahoma. An arctic cold front came through the area on January 25th, ushering in a much colder air mass. High temperatures that day did not crack the freezing mark across most of Northern Oklahoma. Overnight from the 25th into the 26th, the shallow cold air mass advanced further south. By daybreak, on Monday January 26th, temperatures along the Interstate 44 corridor from Lawton, through Oklahoma City, and northeast to Tulsa had fallen back into the mid-20s.

With the surface cold front well south of the area, and an upper level low developing to the west of the area, warm and moist air began flowing from the Gulf of Mexico northward and moving over this shallow cold air mass. Therefore, if you were in Oklahoma City and you went straight up into the air, you would first encounter a very cold air mass, followed by a relatively warm layer of air a few thousand feet up. This relatively warm layer was generally above the freezing mark, so any ice crystals melted as they were falling to the surface. However, the cold air near the ground was cold enough to re-freeze the water either as it hit the ground or other surfaces, or into small ice pellets as they fell through the cold air. The resulting precipitation across most of the area on January 26-27 was a combination of freezing rain and sleet.

After the precipiation had subsided, there was a corridor of significant accumulations of sleet, in excess of 2 inches, from the Walters and Duncan areas, east-northeast through Lindsay, Purcell, Seminole and Wetumka. The greatest sleet accumulations were in Seminole, Hughes, and Pottawatomie Counties, where generally 2 to 4 inches fell, and isolated totals as high as 6 inches were reported.

Because the majority of the precipitation was sleet rather than freezing rain, glaze on trees and power lines did not cause as much damage as other ice storms in recent past. However, the impact to travel was tremendous, and driving in the heavy sleet was extremely difficult. Several hundred automobile accidents occurred across the area. Several days later, satellite images still showed the sleet on the ground (left).

Only about ten days after sleet had melted off the ground in parts of central Oklahoma, a severe weather outbreak affected a good portion of the area. Tuesday, February 10, 2009 began unlike most severe weather days in Oklahoma. The morning low in Oklahoma City at Will Rogers Airport dipped down to 40 degrees, and the temperature was in the 40s for most of the morning commute. In fact, temperatures across all of Oklahoma and Western North Texas ranged from 30 degrees northwest to the mid 50s southeast.

Thunderstorms began developing by midday in parts of central Oklahoma, along the leading edge of deep moisture returning north from the Gulf of Mexico, and a surface front. These storms produced numerous reports of large hail, some up to the size of baseballs (2.75" in diameter) in Piedmont, Yukon, Seward and Guthrie. However, most notably, the storms produced a combined 6 tornadoes, one of them a deadly EF-4 tornado that struck the town of Lone Grove, OK. Another strong tornado struck Edmond, OK earlier in the day.

A detailed web page documenting this event is available on our website.

The month of April was a month of contrasts. Early April saw one of the most significant wildfire outbreaks in recent past on April 9th. A dryline associated with a surface low pressure system swept through Oklahoma during the early afternoon. Rapid drying, and increasing winds, behind the boundary substantially increased the wildfire danger. Many wildfires broke out across western Oklahoma and western North Texas. The image to the right is an infrared satellite image. The dark spots show the location of fires around 6:25pm CDT.

This wildfire event was unusual in that it required Fire Warnings in rapid succession - almost at the pace that we are accustomed to issuing warnings for severe thunderstorms. Fire Warnings are a tool that emergency managers can use to disseminate evacuation orders via the NWS, using NOAA All Hazards Weather Radio. These messages describe the area threatened using well known street names, and provide instructions on which direction or along which roads people should travel to remove themselves from the path of the fire.

At the height of the outbreak, NWS Norman dedicated one meteorologist to the sole task of coordinating and disseminating Fire Warnings. NWS Norman issued eleven Fire Warnings for 8 different communities (some Warnings were updates of previously issued Warnings). The warned communities were all located in Oklahoma, and included Marietta, Wellston, Sparks, Velma, Loco, Midwest City, Bradley, and Lindsay.

This event provided some unique challenges. While one meteorologist was dedicated to issuing Fire Warnings, there were also concerns with severe thunderstorms producing large hail in central Oklahoma, and the threat of damaging non-thunderstorm winds in western Oklahoma, behind a cold front. The diverse combination of hazards (shown in Graphicast to the left) made this a very high impact event across much of the area. The NWS in Norman also provided weather briefings by phone to firefighters, emergency managers, and media partners, almost continuously between 3:00 PM and 9:00 PM CDT. For more on this event, read the NWS Norman newsletter.

The end of April saw a transition to a very wet pattern. Several rounds of thunderstorms brought some severe weather and tornadoes, along with some flooding, starting around April 25th and lasting through the end of the month. There were several tornadoes reported around the area, and even some softball size hail was reported near Lamont.

The biggest story was probably the flooding, especially near the Red River on April 29th. That day, an intense line of thunderstorms bowed out and raced east across parts of southern Oklahoma. It produced estimated wind gusts as high as 90 to 95 mph in Pontotoc County. The southern end of the bow echo stalled and elongated in an east to west fashion, producing hours of torrential downpours near the Red River in southern Oklahoma.

The result was an Oklahoma Mesonet observing station near Burneyville, OK (Love County) recording 12.89" of rain in around 18 hours. Most of this total - 12.42" of rain - fell on the calendar day April 29th. This total broke several records, including the daily record at Burneyville and the daily rainfall record for any Oklahoma Mesonet station since the network’s inception in 1994.

Moreover, the single day total of 12.42 inches was sufficient, on its own, to make April 2009, the wettest month ever observed at the Burneyville station. When you add in the rest of April, the monthly total reached 15.36 inches. National Weather Service observations date back much farther than 1994, and the 12.42 inch daily rainfall at Burneyville ranks as the fourth highest single day amount in Oklahoma history.