(CNN) -- A powerful storm that swept across the country will lose its fury Friday and blow out over the Atlantic by day's end, forecasters said.
The weather system stretched from Canada to the Gulf of Mexico on Thursday, and dumped snow in the north central and northeastern United States.
In the Ohio and Mississippi valleys, it poured torrential rain and spawned tornadoes in the Deep South.
The storm took three lives in separate incidents in Missouri, Mississippi and Nebraska.
A woman froze to death after her car broke down near Berea, Nebraska, when a blizzard struck Monday, state police said. Her son survived, but suffered frostbite and hypothermia, and is at a local hospital.
An employee for Ameren Missouri was electrocuted Thursday while attempting to restore power after storms, the company said.
In Mississippi, one person died in Kemper County, on the Alabama border Thursday, after strong winds destroyed a steel building along a highway, the National Weather Service reported.
Five people were injured in Mississippi, according to the Mississippi Emergency Management Agency.
At least seven counties in Mississippi and four in Alabama suffered damage, officials said.
Georgia's emergency management agency reported trees down in several counties Thursday night.
A weak tornado snapped large limbs and caused power outages around Slidell on Louisiana's Gulf coast, according to the National Weather Service.
Tornado watches remain in effect through Friday morning in parts of Georgia, North Carolina, South Carolina, Alabama and Florida.
Hazardous springtime weather is hardly an anomaly in many of these areas.
A cool March meant that there had been significantly fewer tornadoes this year than last year. But that doesn't mean storms will be less powerful, or that the rest of the season will be slow.
Gov. Jay Nixon declared a state of emergency in Missouri after the series of storms pummeled the St. Louis area and other parts of the state Wednesday night.
Arkansas was also hard hit, prompting Gov. Mike Beebe to declare 15 counties state disaster areas.
CNN's Joe Sutton, Phil Gast, Cristy Lenz, Dave Alsup and Sean Morris contributed to this report.