Gary McManus
Associate State Climatologist
Oklahoma Climatological Survey

The numerous and sometimes violent tornadoes that occurred over the southern United States during the last week were largely absent from Oklahoma. Despite the preliminary count of more than 100 from April 22 to April 25, it appears only one tornado touched down in the state during that period. According to officials from the National Weather Service, a weak tornado touched down near Bryans Corner in Beaver County on April 22. No damage or injuries were reported with the tornado. That brought the tornado count for the year thus far in Oklahoma to three. A couple of tornadoes touched down on March 8 in western Oklahoma, including an EF2-rated twister that damaged parts of the small town of Hammon. Oklahoma normally sees 16 tornadoes through the end of April, including 11 during the current month. The state's tornado season peaks with an average of 20 during May before tapering off over the summer to reach an annual average of 53. Tornado statistics are based on data from 1950 to 2009.

The reason for Oklahoma's muted severe weather season is a combination of climate factors and just sheer luck. The tornadoes that struck in the High Plains of Colorado, Kansas and Texas on April 22 could have very easily occurred in Oklahoma if the storm system that spawned them either sped up or slowed down. Another factor was the strong El Niño that has lingered from the fall into early spring. That climate phenomenon shifted the storm track farther to the south and kept the Southern Plains in a relatively cool pattern. By doing so, it robbed the state of the storm systems and the warm, moist air that are needed to generate and fuel thunderstorms. As El Niño's influence continues to wane and temperatures continue to warm, more opportunities for severe weather will materialize.

A quiet start is not always an accurate indication of what the rest of the severe weather season will look like. Oklahoma also experienced a very quiet January-April in 1998 with only two tornadoes reported. The storm season soon became much more active with 22 tornadoes reported during both May and June. The total for that year ended at 83. That serves as a reminder to stay prepared because the state's fortunes can change rapidly with the next bout of severe weather.