National Weather Service United States Department of Commerce

Tropical Moisture Brings Slight Risk of Excessive Rainfall to the Southwest; Strong to Locally Severe Storms on the Plains

Heavy rain and flash flooding are possible across portions of the Southwest through Friday, where Flood Watches are in effect. Strong to locally severe thunderstorms are possible today across portions of the Plains. A tropical wave is causing heavy rainfall in Puerto Rico and the Virgin Islands, which may cause urban and small stream flooding and landslides today. Read More >

March 23 banner


On March 23, 2012 low pressure spinning over Missouri sent waves of showers and thunderstorms eastward through the Ohio Valley for much of the day.  By early afternoon a pocket of strong winds aloft rotated around the low and entered Kentucky just as a small line of convection developed roughly along Interstate 65.  As the line of showers moved to the northeast, it may have crossed a subtle boundary that helped add just enough spin to the atmosphere to allow a couple of very narrow, brief tornadoes to form.  The cells that spawned the tornadoes were very small, reaching only about 20,000 feet into the atmosphere (summertime supercells can grow to more than 50,000 feet tall).  There wasn't even any lightning, as evidenced by lightning detection networks as well as storm witnesses who reported no thunder before the tornadoes struck.

On the map below, click on a track (thick red line) to see detailed information about each tornado in Jefferson and Shelby Counties.