'Historic' flooding threaten these US states: See maps
This story was updated to add new information.
Meteorologists predict Friday will see the Midwest and mid-South continue to be hit by a devastating storm system that has unleashed tornadoes and heavy rains, causing a "catastrophic and potentially historic flash flood event."
In just five days, parts of a 1,000-mile span from Texas to Ohio will see up to four months' worth of rain, according to AccuWeather.
The storms, fueled by a stagnant atmospheric river, unleashed tornadoes Wednesday night and Thursday from Arkansas to Illinois, flattening homes, destroying businesses and overturning semi-trucks. Tennessee Gov. Bill Lee said in a Thursday evening news conference that swaths of the town of Selmer were "completely wiped out."
Extended rainfall could overwhelm waterways
Some locations across Arkansas, Missouri, Kentucky and Tennessee could get 8 to 12 inches of rain over several days, with local totals topping 16 inches, according to AccuWeather meteorologists.
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The rush of rainfall will be too much for urban areas' small streams and drainage systems to handle. Rainfall rates of up to a few inches an hour could cause flash flooding.
“Do not let your guard down. Intense rainfall rates, overwhelming rainfall totals and a surge of water moving downstream could lead to life-threatening flash flooding in places where people have never seen it flood in their lifetime,” AccuWeather chief meteorologist Jonathan Porter said in a news release.
Where flood gauges will be put to the test
The National Oceanic and Atmospheric Administration's National Water Prediction Center has forecast that areas in Arkansas, Illinois and Missouri could expect major flooding. The total water level rise in the region's streams and rivers, however, may not be fully reflected in NOAA's river gauge projections until the rain event is fully started.
Higher river level forecasts are expected to gradually increase until the end of the week, according to AccuWeather.
Be prepared for severe weather
AccuWeather predicts severe weather will increase into April and May as temperatures warm.
Throughout the severe weather season, the National Weather Services encourages people to be prepared. Among the agency's suggestions: Go over safety plans with family members and co-workers, and make sure storm shelters and safe rooms are stocked with supplies such as flashlights, bottled water, snacks and a first-aid kit.
CONTRIBUTING Doyle Rice and Christopher Cann