The East Coast is bracing for a snow and ice storm that's threatening to smash into the region right as the nation gears up for its busiest travel day of the year.
Even the balloons in New York's Macy's Thanksgiving Day Parade might fall victim to the winter weather, as organizers said they were considering grounding them if conditions become too threatening on Thursday morning.
The deadly storm, which began on the West Coast last week, is gathering steam as it heads toward the mid-Atlantic and northeast. Flights were operating with few delays or cancellations, but forecasters were expecting the weather to worsen Wednesday.
"The timing of the storm couldn't be worse," said Chris Vaccaro, spokesman for the weather service headquarters in Silver Spring, Md. "We are seeing numerous threats as the storm is beginning to develop and intensify."
Vaccaro said heavy rain and high winds would impact travel by air and road in the northeast and mid-Atlantic, and that the weather in that part of the country could have a ripple effect on airports with departing and originating flights elsewhere.
On Wednesday morning, heavy rain and breezy conditions will strike the East Coast, with ice and snow a possibility in the Appalachians, western Pennsylvania and western New York. Snow totals from the Ohio Valley to the interior of the Northeast were expected to be less than 10 inches, the weather service said.
Meanwhile, organizers of the Macy's Thanksgiving Day Parade are considering grounding balloons for the first time since 1971 if if winds exceed 23 mph and gusts exceed 34 mph. The rules were put into place after fierce conditions in 1997 caused a Cat in the Hat balloon to topple a light pole, seriously injuring a woman spectator.
Current forecasts call for sustained winds of 20 mph and gusts of 36 mph.
The storm sprung out of the West and has been blamed for at least 11 deaths, half of them in Texas. It limped across Arkansas with a smattering of snow, sleet and freezing rain that didn't meet expectations.
But the system packed plenty of punch as it moved eastward.
John Robinson, the warning coordination meteorologist at the National Weather Service in North Little Rock, said winter storm warnings were issued for parts of the eastern half of the United States through Wednesday afternoon.
Some of the country's busiest airports — New York, Washington, D.C., Philadelphia, Boston and Charlotte, N.C. — could see big delays at one of the peak travel times of the year.
This holiday will likely see the most air travelers since 2007, according to Airlines for America, the industry's trade and lobbying group, with the busiest day being Sunday, an estimated 2.56 million passengers. Wednesday is expected to be the second-busiest with 2.42 million passengers.
Ninety percent of travelers this week will drive, according to AAA, and an estimated 38.9 million people — 1.6 percent fewer than last year — are expected to drive 50 miles or more from their home.
In New Jersey, officials advised travelers to check with their airlines and reduce speed on highways as a winter weather advisory was set to take effect shortly before midday across the state's northwest areas.
Meanwhile, forecasters were predicting 5 to 8 inches of snow in Buffalo, more in the northern Adirondacks, and a winter storm watch was posted for central New York state with heavy rain expected in parts of the Hudson Valley.
In the nation's capital, federal agencies opened Tuesday though the National Weather Service issued a winter weather advisory for the northern and western suburbs of Washington, D.C., and Baltimore, amid forecasts of a light mix of snow, sleet and freezing rain that could be topped off by heavy rain.
The U.S. Office of Personnel Management, which sets leave policies for 300,000 federal workers in Washington, said that while government was open Tuesday, employees could take unscheduled leave or unscheduled telework.
Jeff Smidt hopes to travel from his home in Toronto on Wednesday to visit his family near Boston. He plans to drive if he cannot fly.
"My understanding is that I'm traveling at like the worst time ever," Smidt said. He tried to change his JetBlue reservation to get on an earlier flight but was told the airline wasn't waiving any change fees yet.
"Worst comes to worst, it will be an eight-hour trek down Interstate 90," he said.
The Associated Press contributed to this report.