(CBS News)-- MOBILE, Ala. An enormous storm system that dumped snow and sleet on the nation's midsection and unleashed damaging tornadoes around the Deep South began punching its way toward the Northeast on Wednesday, slowing holiday travel.
Post-Christmas travelers braced for flight delays and a raft of weather warnings for drivers, a day after rare winter twisters damaged buildings in Louisiana and Alabama.
Snow and ice covered roads in southern Illinois and southern Indiana early Wednesday. Officials urged residents to stay home if they can. State police reported numerous slide-off accidents in the Evansville, Ind., area and white-out conditions on Interstate 64 in Indiana with wind gusts around 30 mph.
The heaviest snows were being seen in parts of Indiana and Ohio, where blizzard conditions are expected to drop accumulations of more than one foot, reports CBS station WFOR-TV meteorologist Jeff Berardelli. Snow is also beginning to fall in Pennsylvania and northern Virginia and could intensify in those states, along with western New York, throughout the day.
On the southern edge of the front, severe weather is expected in Georgia and the Carolinas.
The storm system headed from the Gulf Coast to New England has been blamed for three deaths and several injuries, though no one was killed outright in the tornadoes. The storms also left more than 100,000 without power for a time across the South, darkening Christmas celebrations.
Thirty-four tornadoes were reported in Texas, Louisiana, Mississippi and Alabama during the outbreak Tuesday, the National Weather Service said.
Rick Cauley's family was hosting relatives for Christmas when tornado sirens went off in Mobile. Not taking any chances, he and his wife, Ashley, hustled everyone down the block to take shelter at the athletic field house at Mobile's Murphy High School in Mobile.
It turns out, that wasn't the place to head.
"As luck would have it, that's where the tornado hit," Cauley said. "The pressure dropped and the ears started popping and it got crazy for a second." They were all fine, though the school was damaged, as were a church and several homes, but officials say no one was seriously injured.
Camera footage captured the approach of the large funnel cloud.
"We were in the stock room. It literally came through the parking lot, and we ran into the cooler," Walmart store manager Joshua Holman told CBS affiliate WKRG. "I think it came like right literally in the front of the store."
Mobile was the biggest city hit by numerous twisters. Along with brutal, straight-line winds, the storms knocked down countless trees, blew the roofs off homes and left many Christmas celebrations in the dark. Torrential rains drenched the region and several places saw flash flooding.
More than 325 flights around the U.S. were canceled as of Wednesday morning, according to the flight tracker FlightAware.com. The cancelations were mostly spread around airports that had been or soon would be in the path of the storm.
Holiday travelers in the nation's much colder midsection battled treacherous driving conditions from freezing rain and blizzard conditions from the same fast-moving storms. In Arkansas, highway department officials said the state was fortunate the snowstorm hit on Christmas Day when many travelers were already at their destinations.
Texas, meanwhile, dealt with high winds and slickened highways.
On Tuesday, winds toppled a tree onto a pickup truck in the Houston area, killing the driver, and a 53-year-old north Louisiana man was killed when a tree fell on his house. Icy roads already were blamed for a 21-vehicle pileup in Oklahoma, and the Highway Patrol there says a 28-year-old woman was killed in a crash on a snowy U.S. Highway near Fairview.
Trees fell on homes and across roadways in several communities in southern Mississippi and Louisiana. Mississippi Gov. Phil Bryant declared a state of emergency, saying eight counties reported damages and some injuries.
It included McNeill, where a likely tornado damaged a dozen homes and sent eight people to the hospital, none with life-threatening injuries, said Pearl River County emergency management agency director Danny Manley.
The snowstorm that caused numerous accidents pushed out of Oklahoma late Tuesday, carrying with it blizzard warnings for parts of northeast Arkansas, where 10 inches of snow was forecast. Freezing rain clung to trees and utility lines in Arkansas and winds gusts up to 30 mph whipped them around, causing about 71,000 customers to lose electricity for a time.
Christmas lights also were knocked out with more than 100,000 customers without power for at least a time in Texas, Arkansas, Oklahoma, Mississippi, Louisiana and Alabama.
Blizzard conditions were possible for parts of Illinois, Indiana and Kentucky up to Cleveland with predictions of several inches to a foot of snow. By the end of the week, that snow was expected to move into the Northeast with again up to a foot predicted
Jason Gerth said the Mobile tornado passed by in a few moments and from his porch, he saw about a half-dozen green flashes in the distance as transformers blew. His home was spared.
"It missed us by 100 feet and we have no damage," Gerth said.
In Louisiana, quarter-sized hail was reported early Tuesday in the western part of the state and a WDSU viewer sent a photo to the TV station of what appeared to be a waterspout around the Lake Pontchartrain Causeway in New Orleans. There were no reports of crashes or damage.
Some mountainous areas of Arkansas' Ozark Mountains could get up to 10 inches of snow, which would make travel "very hazardous or impossible" in the northern tier of the state from near whiteout conditions, the weather service said.
The holiday may conjure visions of snow and ice, but twisters this time of year are not unheard of. Ten storm systems in the last 50 years have spawned at least one Christmastime tornado with winds of 113 mph or more in the South, said Chris Vaccaro, a National Weather Service spokesman in Washington, via email.
The most lethal were the storms of Dec. 24-26, 1982, when 29 tornadoes in Oklahoma, Missouri, Arkansas, Tennessee and Mississippi killed three people and injured 32.
In Mobile, a large section of the roof on the Trinity Episcopal Church is missing and the front wall of the parish wall is gone, said Scott Rye, a senior warden at the church in the Midtown section of the city.
On Christmas Eve, the church with about 500 members was crowded for services.
"Thank God this didn't happen last night," Rye said.
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