A massive storm system is forecast to bring snow, rain, floods, wind and severe weather to much of the central, eastern and southern U.S. on Wednesday and Thursday.
On the cold side of the storm, snow is likely Wednesday and into Thursday from northern Texas to northern New England, AccuWeather said.
Meanwhile in the South, more than 20 million people are at risk of severe weather, including a threat of tornadoes, on Thursday, according to the Storm Prediction Center.
By Friday, the storm should be exiting the Eastern Seaboard, Weather.com said. Mainly rain is expected all the way up the Northeast coast to Maine, given the milder air ahead of the system.
Here's when and where you can expect the storm:
Snow forecast for Chicago, Detroit
Winter storm warnings have been issued across portions of the upper Midwest, including central Missouri and northern Illinois, as the storm approaches.
The snow will begin to arrive in the Plains late Wednesday and progress northeastward, impacting Chicago in the early hours of Thursday, according to AccuWeather. Forecasters say snow will expand into Detroit later Thursday and deliver anywhere from 3 to 6 inches of snow to the Motor City.
Snow could be heavy at times in parts of the Midwest, Weather.com said. The National Weather Service warned that snowfall rates could exceed 2 inches per hour at times.
On the northwestern edge of the storm, gusty winds will pick up snow and limit visibility, with a period of localized whiteout or blizzard conditions not out of the question, AccuWeather said.
What is lake effect snow? Here's how it happens and how much snow it can bring with it.
With heavy rains, forecasters warn of flooding risk
Up to 3 inches of rain could fall from northeastern Oklahoma to western New York and as far southeast as northern Georgia, forecasters warned. Snow already on the ground in these areas is expected to melt with the warmth and downpours and lead to river and stream flooding, AccuWeather said.
A "slight risk" (Level 2 of 4) of excessive rainfall is in effect from southern Illinois to western New York, as well as over parts of the southern Appalachians on Thursday, the National Weather Service said. These areas are expected to have the greatest chances for flash flooding.
South faces severe weather, tornado threat
Beginning late Wednesday and continuing into early Thursday, much of Oklahoma and north Texas will also be at risk of severe weather.
Meanwhile on Thursday, more than 20 million people are in a zone that’s most at risk of severe weather, the Storm Prediction Center said.
The region includes Little Rock, Arkansas; Memphis and Nashville in Tennessee; Louisville, Kentucky; Jackson, Mississippi; and Birmingham, Alabama.
Some of the storms could become “supercellular," capable of producing damaging wind gusts and tornadoes, the Storm Prediction Center said. Stronger heating of the atmosphere in some areas will lead to a greater tornado threat.
Contributing: The Associated Press
This article originally appeared on USA TODAY: Winter storm warnings in Midwest; Severe weather forecast for South