The massive , blamed for at least 14 deaths in the Plains and West, is parked over the East Coast Wednesday, halting Thanksgiving traffic with snow, ice, heavy rains and even a tornado.

"The timing of the storm couldn't be worse," said Chris Vaccaro, spokesman for the National Weather Service headquarters in Silver Spring, Md. "We are seeing numerous threats as the storm is beginning to develop and intensify."

Heavy rain and breezy conditions were to strike the East Coast from the Carolinas to the Northeast on Wednesday, with ice and snow a possibility in the Appalachians, western Pennsylvania and western New York.

(MORE: )

Boreas will bring snow and even ice in the Northeast, with the heaviest snow in the interior Northeast. In the mid-Atlantic and South, the storm will bring heavy rain and high winds.

"The biggest impact have been on air travel. Road travel impacts aren't that bad right now.," said Tom Niziol, winter weather expert at The Weather Channel. “On the cold/snowy side, it’s underachieving, but on the rain side, that’s about what we expected."

Delays of almost two hours were already being felt at Philadelphia Airports and LaGuardia Airport in New York. Other delays are expected at some of the country's busiest airports.

Most airlines are hoping the storms won't be too severe, allowing them to continue operating a nearly full schedule with few cancellations, but likely a lot of delays, said Daniel Baker, CEO of FlightAware, a global flight tracking service.

"Cancellations are used as a good, preventative measure to avoid cascading delays that can negatively impact travelers thousands of miles away," Baker said.

(MORE: Flight Tracker)

"You'll see 5-8 inches of snow in the Upper Adirodack but other places will get mainly 1-3 inches," said Niziol. "The Appalachians could see 3-5 inches and the ski areas will be happy."

More than 43 million people are to travel over the long holiday weekend, according to AAA. The overwhelming majority - about 39 million people - will be on the roads. But more than 3 million people are expected to filter through airports.

A pedestrian walks amidst the snow showers along Penn Ave on November 26, 2013 in Pittsburgh, Pennsylvania. (Photo by Jeff Swensen/Getty Images)

"The good news is Boreas is moving fast," said meteorologist Stephanie Abrams. "By tonight, it will mostly be done."

Northeast Impacts: Snow and Ice

The interior Northeast and areas on the Great Lakes will see the heaviest portion of snow.

Power outages are being reported in western New York, due to the heavy, wet snow.

"We have 3-5 inches of snowfall in Buffalo this morning," said meteorologist Reynolds Wolf, reporting from Buffalo, N.Y. "Over by the Bills stadium they had 8-10 inches of snow but generally its 3-5. Cars are zipping along on the roads. We’ve not heard any reports of icing but be careful on the roads. Flights are moving well out of Buffalo."

Maryland State Police are declaring a snow emergency in far western Maryland due to deteriorating driving conditions, the Associated Press reports. As of 2:15 p.m. Wednesday, parking is prohibited on roads designated as snow emergency routes in Garrett County.

Treacherous travel conditions are expected in the region. Forecasts call for high winds and snow accumulation of up to 6 inches by Thursday morning.

(MORE: )

After Boreas moves out tonight, the region will face another round of snow. This time, in the form of a lake effect snow event, according to Niziol.

South Impacts: Rain and Severe Weather

A preliminary EF2 tornado touched down in Atlantic Beach, N.C. Tuesday evening according to the National Weather Service. The Emergency Services director reported roof damage to several structures including a hospital. Fifteen people were displaced, but there were no serious injuries.

Officials in Ocracoke Island, N.C. reported a waterspout came ashore shortly after midnight and broke two electric poles on the north end of the island, knocking out power.

MORE ON WEATHER.COM: Winter Storm Boreas

Traffic on I-35 at the 33rd street bridge in Edmond Sunday, Nov. 24, 2013. (Doug Hoke/The Oklahoman)