National Weather Service United States Department of Commerce

Tracking Storm System Across the Eastern U.S.

A storm system will continue to produce widespread showers and thunderstorms as it progresses eastward across the central U.S. into the Northeast through the weekend. There are risks of severe thunderstorms and excessive rainfall on Saturday from the Ozarks into the mid-Mississippi River Valley with potential for damaging winds, large hail, tornadoes, and flash flooding. Read More >

 

Definitions of Flood and Flash Flood


Flood: An overflow of water onto normally dry land. The inundation of a normally dry area caused by rising water in an existing waterway, such as a river, stream, or drainage ditch. Ponding of water at or near the point where the rain fell. Flooding is a longer term event than flash flooding: it may last days or weeks.
 
Flash flood: A flood caused by heavy or excessive rainfall in a short period of time, generally less than 6 hours. Flash floods are usually characterized by raging torrents after heavy rains that rip through river beds, urban streets, or mountain canyons sweeping everything before them. They can occur within minutes or a few hours of excessive rainfall. They can also occur even if no rain has fallen, for instance after a levee or dam has failed, or after a sudden release of water by a debris or ice jam.