Just as the Thanksgiving holiday approaches, an untimely winter storm is expected to sweep through much of the East Coast on the busiest travel day of the year.

Forecasters predict that the ill-timed storm system will form off the coast of Florida on Tuesday night and head up the coast to New England from Wednesday through Thursday morning. As a result, a winter storm watch will be in effect on Wednesday, while the Maryland State Highway Administration is encouraging travelers not to drive that day.

"Wednesday is probably the worst travel day, and it just so happens that we have a coastal low that will be moving up the coastline," said meteorologist Ross Dickman, head of the National Weather Service in New York City, according to the Los Angeles Times. "Travel is going to be an absolute nightmare for people trying to leave Wednesday afternoon."

Due to the weather conditions, secretary and chief executive of the Massachusetts Department of Transportation Frank DePaola warned that "the highways will be more congested than normal," reports the Boston Globe.

The storm, which is described as a classic nor'easter, is expected to bring as much as a foot of snow to some parts of New England, and could cause temperatures to drop to freezing or below the freezing mark in New York and New Jersey.

In New York, the weather system will start as rain before changing over to snow around noon on Wednesday, said David Stark, a National Weather Service meteorologist. As a result, residents in the northern part of New York City can expect 4 to 6 inches of snow accumulation, while those in lower Manhattan may see 2 to 4 inches.

"It is going to be all snow for a good chunk of the afternoon and early evening, not ending until midnight," said Stark.

However, the snow and rain are expected to clear out by Thursday morning, just in time for the annual Thanksgiving Day Parade in Manhattan. Temperatures will be around 40 degrees, but the windchill factor will make the temperature feel around 20 degrees.

Many parts of Massachusetts are also under a winter storm watch for Wednesday morning through Thursday morning. According to the National Weather Service in Boston, the nor'easter could bring 6 to 10 inches of snow in the interior of Massachusetts after a mix of rain and snow transitions to all snow.

As a result, State Police spokesman David Procopio is encouraging travelers to avoid driving Wednesday if possible.

"People should, if at all possible, get their travel done tomorrow," Procopio said. "If not, then be prepared on Wednesday to leave a little bit of extra time, to take care on the roads."

In Washington D.C., there may be a period of light snow at the end of the storm, said Andy Woodcock, a weather service meteorologist in Virginia.

Meanwhile, temperatures will drop 3 to 5 degrees below normal in the upper Midwest to the U.S. Gulf Coast, said Matt Rogers, president of Commodity Weather Group LLC in Bethesda, Maryland.

In addition, Chicago may get some light snow over the next few days.