Tennessee tornadoes

It was a night to huddle in the basement and cower in the face of nature's incredible fury throughout Tennessee last night, as another wave of deadly twisters swept through a state already reeling from last Sunday's 24 tornado deaths. At least 31 tornadoes touched down yesterday, killing 11 and creating tremendous destruction in the Nashville area. Sumner County, just north of Nashville, suffered eight dead. You can see the impressive line of storms that swept through the area in this 3-hour radar animation (1.4 Mb). The breadth, intensity, and duration of the storms covering the Tennessee Valley yesterday and last night was truly impressive to behold. With the peak of tornado season still a month away, the three major tornado outbreaks so far this year have already killed 49 people, compared to the average of 45 killed during the entire year each of the previous three years. Through the end of March, 286 tornadoes hit the United States, compared to an average of 70 for the January-March period in each of the past three years.

Severe thunderstorms from last night's onslaught will continue to affect Florida, Alabama, and Georgia today, but the risk of tornadoes is much reduced. It appears that the coming week will be much quieter,with no major tornado outbreaks likely. However, the jet stream pattern remains very active over the coming two weeks, and another major tornado outbreak during the week following Easter is a stong possibility. The tornado season of 2006 is more than making up for the quiet tornado seasons we've been blessed with the past three years!


Figure 1. Radar snapshot of the tornadic thunderstorms that swept through Tennessee yesterday. Note the classic hook-shaped echo from the cell southwest of Nashville, indicating a tornado.

Jeff Masters