Even with the timing and severity of the blast of freezing precipitation uncertain, officials from parts of Texas to southeastern Virginia warned motorists to stay off the roads. Popular warm-weather tourist destinations — Charleston, S.C.; Savannah, Ga.; Pensacola, Fla.; Virginia Beach, Va.; and New Orleans — expected ice and snow over the next two days, rare occurrences in places that seldom even see prolonged sub-freezing temperatures.
At an Ace Hardware store in the north Georgia town of Cumming, snow shovels were in short supply, but manager Tom Maron said feed scoops - often used in barns - could be substituted. Workers expected brisk business, with patrons buying insulation, faucet covers, portable heaters and other cold-weather gear.
"We're fixing to put the ice melt out, and we've got plenty of sand here to mix in," Maron said shortly before dawn.
Much of Georgia was placed under a winter storm watch for Tuesday and Wednesday, with some areas forecast to see as much as 3 inches of snow. But Jason Deese with the National Weather Service said the snow totals would "matter very little in this situation because of the ice potential."
"Some parts of the state may end up seeing the greatest impact just because they get more ice than snow," he said.
In rural Mississippi, amid warnings about snow and ice, four people died when an early morning fire destroyed a mobile home in Itawamba County, near the Alabama border. Investigators believe a space heater was to blame, and local officials said it was bitterly cold overnight, with temperatures dipping to about 20 degrees. Sheriff Chris Dickinson said nine people were in the mobile home at the time, using the heater for warmth. Officials didn't identify the victims but said they ranged in age from 3 months to 30 years.
Snow began falling before dawn Tuesday in the extreme northwest portion of Alabama. In Montgomery, Bradley Thrift sat in a hotel parking lot letting his truck warm up before heading out with a crew to work on sewers.
"We've got a job to do. We'll just be out in it," said Thrift, wrapped up in a thick coat. "We'll be safe. When the boss man says that's it, it's too slippery, we'll just come back here and wait."
At a nearby Publix grocery story, shoppers had cleaned out three shelves of bottled water, and all the boxed fire logs were gone. The milk cabinet had big gaps where rows of gallon jugs were missing.
"We kept having to replenish the milk yesterday — people were buying it so quickly," worker Jeneen Gabson said.
In the Hampton Roads area of Virginia — which forecasters said could see a foot of snow — store shelves started emptying of staples such as bread by Monday night. Schools and businesses planned to close early, with the storm expected to further clog an already-busy afternoon commute.
In coastal Charleston, it was a balmy 62 degrees Monday. But the approaching weather led the College of Charleston to cancel classes Tuesday. There was a forecast of rain, and sleet in the late afternoon, with the first snow expected Wednesday morning.
Nationwide, nearly 3,000 flights within, into or out of the U.S. had been cancelled by 9 a.m. Tuesday, according to statistics from the flight tracking service FlightAware. Only a couple of hundred flights are canceled in the U.S. on a typical day.
The airport hardest-hit by cancellations Tuesday was also the world's busiest: Hartsfield-Jackson Atlanta International, where a total of 863 inbound and outbound flights had been cancelled by 9 a.m. Tuesday, according to FlightAware.
Meanwhile, in the Midwest, plummeting temperatures and increasing winds took root for another day even as the storm moved south. Several states in the central U.S. saw schools and other facilities close for a second consecutive day as dangerous wind chills were predicted. In Minnesota, forecasters said wind chills could reach 35 to 50 degrees below zero.
In the Carolinas, many school districts were running on half-day schedules Tuesday so students could head home before the worst of the storm system hit. In North Carolina's Outer Banks, barrier islands that are popular with tourists during the warm seasons, residents were bracing for as much as 8 inches of snow.
Several inches also were expected in South Carolina, where the state department of transportation planned to send crews out Tuesday to treat roads with sand and brine to ease any troubles caused by ice.
In Louisiana, state Public Service Commission Chairman Eric Skrmetta told residents to be prepared by stocking up with food, fueling cars and making sure to have cash on hand. State police said freezing rain was falling in the central part of the state early Tuesday, but most highways remained open. The heaviest snowfall was likely to be 1 to 3 inches just north of the Baton Rouge metro area
Donna Vidrine, a cashier at Simcoe Food World in Lafayette, said her store was already busy Monday.
"They're buying things like canned goods — nonperishable items — and bottles of water and diapers for their baby," she said.
In Livingston Parish in southeast Louisiana, authorities said a curfew would be in effect Tuesday night and Wednesday morning because of the threat of freezing rain. Sheriff Jason Ard said motorists in the parish should stay off roadways, except essential personnel and first responders.
Associated Press writers Jay Reeves in Montgomery and Janet McConnaughey in New Orleans contributed to this report.
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