Thousands of flights were canceled, angry storms and tornadoes tore through several Southern states, and the Northeast was bracing for up to 20 inches of snow Thursday as a gnarly winter storm roared east.

The storm front caused at least two fatalities and several injuries across a dozen states, destroying mobile homes in Alabama and Mississippi and prompting flooding and mudslides in states from the South to the Appalachian region.

Tornado watches were in effect Thursday evening from northern Florida up through North Carolina, and heavy rains brought travel delays and school closures.

In Kentucky, states of emergency were declared in Bell and Harlan counties amid rock slides and water rescues. Two mobile homes floated away as dozens of families were evacuated amid rising water, authorities said.

“It's a very bad situation that continues to worsen by the hour,” Harlan County Judge Executive Dan Mosley said.

At Hartsfield-Jackson Atlanta International Airport, more than 1,200 flights in and out were delayed by midday.

In North Carolina, the FAA evacuated the control tower at Charlotte Douglas International Airport because of a tornado threat. More than 400 flights were canceled. Operations later resumed after an airfield inspection showed no damage.

Heavy rain, high winds and possible tornadoes slammed across parts of Mississippi, Louisiana, Alabama, Tennessee, Kentucky and the Carolinas on Wednesday and Thursday, flooding homes, knocking down trees and blocking roads. More than 172,000 homes and businesses were without power across the region Thursday, and the Friday forecast called for more rain.

The weather service confirmed that an 800-foot-wide tornado had torn through Yazoo County, Mississippi, toppling trees and damaging homes.

A tornado also hit the Birmingham suburb of Helena, Alabama. One death was reported in the state when high winds smashed mobile homes near Demopolis.

In northern Alabama, flooding forced rescuers to suspend their search for a vehicle that disappeared with a person inside it in north of Buck’s Pocket State Park.

“As the car started shifting because of the water, we noticed what appeared to be an arm reaching out,” witness Kirkland Follis, who called 911, told WHNT-TV.

Flooding also swamped streets at the University of Alabama in Tuscaloosa, and scores of school districts across the state canceled classes.

A second death because of the storms was reported in South Carolina, as a driver was killed when a tree fell on an SUV near the town of Fort Mill, authorities said. Across the state in Spartanburg, a possible tornado left behind a string of damaged buildings captured by photos on social media.

In Tennessee, a woman was killed and four people were injured when a rain-soaked tree fell on a van carrying Sevierville city employees, officials said. The accident appeared to be caused by the weather but was still under investigation.

Tornado warnings were in effect in the Atlanta suburbs and at the University of Georgia in Athens.

The storms were expected to continue into Friday, said AccuWeather senior meteorologist Isaac Longley. Some areas in the South and up into Maryland could see 3 to 5 inches of rain, he said.

"The main threat going forward in the Southeast will be the winds, really damaging wind gusts of up to 60, 80 miles per hour," he told USA TODAY. "There will also be heavy rains as we deal with a lot of moisture from the Gulf of Mexico."

Farther north, a winter storm was rolling in after a whirlwind trip across much of the Midwest and Southwest that featured snow as far south as the Mexican border in El Paso, Texas. A mix of rain, freezing rain and sleet in parts of New York state and New England was forecast to become a howling snowstorm before concluding Friday, Longley said. Some areas could see up to 3 inches of snow an hour.

"In northern New York up to Vermont and Maine you could see locally up to 20 inches of snow depending on where the snow bands set up," Longley said.

The wintry storm system comes just days after springlike warmth across the East.

"This winter has been all over the place, it can't seem to make up its mind," Longley said. "But it looks like we are getting into more of a winter trend."

Contributing: The Associated Press

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