Gerald Herbert/Associated Press
People inspect a business in Slidell, Louisiana, that was severely damaged by Wednesday's severe storms.
CNN
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A potentially dangerous storm is poised to hit parts of the Southeast and the Ohio Valley Thursday, a day after deadly storms ripped through Texas and Mississippi, causing tornadoes and flash flooding.
Life-threatening flash flooding was reported early Thursday morning in the Tallahassee, Florida area, with water invading buildings and rescue efforts underway, the National Weather Service said.A flash flood emergency was issued for the area until 6:30 a.m.
The National Weather Service in Tallahassee warned that “significant flash flooding is already occurring.” “Move to higher ground now! This is an extremely dangerous and life-threatening situation. Do not attempt travel unless you are evacuating an area at risk of flooding or under an evacuation order. ”
This severe storm system is expected to reach its peak on Wednesday before losing power on Thursday. At least four tornadoes touched down in Louisiana and Texas, and some parts of the Gulf Coast reported that the storm caused life-threatening flooding, widespread power outages and damage to homes and businesses.
Gov. Tate Reeves said Wednesday that one death has been reported so far in Scott County in central Mississippi.
According to the Storm Prediction Center, there will be a slight risk of severe thunderstorms (Level 2 out of 5) from Florida to South Carolina on Thursday as the storm moves east. The main threats are wind damage and heavy rain, but a tornado or two is also possible.
Although the severe threat is decreasing across the south, strong winds remain in much of the region, with more than 30 million people under wind advisories.
“High winds may blow around unsafe objects. Tree branches may be blown away and several power outages may occur,” the Bureau of Meteorology warned.
Widespread homes and businesses are left in darkness after the storm blows through. As of midnight Wednesday, about 260,000 people were without power from Texas to Georgia, according to PowerOutage.us.
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Further north, there is a risk of severe thunderstorms in the Ohio Valley Thursday afternoon/evening at Level 3/5. These deluges could be even more impactful than storms to the south.
Multiple tornadoes and hail are possible in the most dangerous area, which stretches from western West Virginia to eastern Ohio. Surrounding areas, including eastern Ohio and parts of Pennsylvania and Kentucky, also could experience strong storms, although the risk is less severe.
Most of the severe storm is expected to move offshore by Friday, but parts of northern New England will still be at risk of flooding as the storm moves through the Great Lakes and interior Northeast.
On Wednesday, the storm bulldozed from Texas to Mississippi, leaving damage and destruction in its wake.
An EF-1 tornado struck Slidell, Louisiana, injuring at least 10 people, police said. Slidell police spokesman Daniel Suznow said the storm littered city streets with trees and power lines, and rising water levels prompted first responders to organize water rescue operations.
Tornadoes also touched down near St. Francisville and Lake Charles, Louisiana, according to the National Weather Service.
Another EF-1 tornado struck a series of businesses in the Houston suburb of Katy, Texas. No injuries were reported Wednesday, but the storm damaged a strip mall and a nearby auto repair shop, National Weather Service meteorologist Jeffrey Evans said. Images show a large portion of the store's roof collapsed onto the parking lot, surrounded by debris and metal debris.
Gerald Herbert/Associated Press
Firefighters clear debris left in the aftermath of the storm in Slidell, Louisiana.
The Mississippi Office of Emergency Management announced Wednesday that more than 70 homes across Mississippi were reported damaged or destroyed.
Torrential rains also caused dangerous flooding in parts of Texas and Louisiana, with authorities rushing to provide water rescues as roads turned into rivers.
Unusual rainfall in New Orleans overwhelmed the city's complex water pump network and other aging flood mitigation infrastructure, causing water to spill onto streets, according to the city's Sewerage and Water Commission.
New Orleans set one of several daily rainfall records set across the South on Wednesday. The city's Louis Armstrong International Airport received 6.44 inches, nearly triple the previous record.
Louisiana officials closed nearly a dozen school districts and several state offices and city buildings on Wednesday in preparation for the storm.
The disruption spread further east as the storm moved into Alabama and Georgia, causing the Masters to delay the gate opening of Augusta National Golf Course on Wednesday.
CNN's Taylor Ward, Mary Gilbert, Carol Alvarado, Sara Smart, Rachel Ramirez, Jacob Lev, Rosa Flores, Sara Weisfeldt, Devon Sayers and Rebekah Riess contributed to this report.