A quick change to colder weather could be accompanied by accumulating snow from the southern Appalachians to southeastern New England spanning late Wednesday night into Thursday.
Just hours after record-challenging warmth occurs, temperatures will plunge 15 to 30 degrees Fahrenheit from the interior South to the northeastern United States during Wednesday night and into Thursday morning.
The storm will begin as rain in most areas.
Despite the warmth into midweek, there is the potential for snow to fall at a fast enough pace to lead to slippery roads and airline delays as the storm progresses.
Major cities at risk for a period of accumulating snow include Pittsburgh, Washington, D.C., Baltimore, Philadelphia, New York City and Boston.
The storm could affect heavily-traveled stretches of Interstate 64, I-66, I-68, I-70, I-76, I-78, I-80, I-81, I-83 and I-95.
As the cold air moves in, a storm will trek from the southern Plains to off the Atlantic coast.
"If the storm develops to its full potential and cold air comes in fast enough, there may be a swath of heavy, wet and accumulating snow from the mountains of Virginia and West Virginia to the Delaware, New Jersey, New York and southeastern New England coasts," according to AccuWeather Meteorologist Mike Doll.
In this case, major travel delays and disruptions to daily activities could result with accumulations ranging from a slushy coating to as much as 8 inches. The snow could fall at the rate of 1 to 2 inches per hour.
In some areas, the snow may begin to fall before daybreak on Thursday. In some locations, the snow can begin to fall as motorists begin their commute on Thursday.
By Thursday morning, temperatures could be within a few degrees of freezing in a large swath of the mid-Atlantic states. The setup could cause rain to change to snow.
The exact track of the storm will determine where the swath of accumulating snow occurs.
"The swath of accumulating snow is likely to be in a narrow southwest to northeast band with the challenge being exactly where that band sets up," according to AccuWeather Senior Meteorologist Brian Wimer.
"If the storm takes a more northern path, then the heaviest snow would occur from parts of Kentucky and northern West Virginia to Pennsylvania, northern New Jersey, southeastern New York state and central New England," Wimer said.
In this scenario, mild air will hold on a bit longer with temperatures staying well above freezing until the storm passes from the southern Appalachians to southeastern New England.
If the storm takes a more southern route, then snow could fall on parts of North Carolina, southeastern Virginia, the lower part of the Delmarva Peninsula, Long Island, New York and Cape Cod, Massachusetts.
In this scenario, colder air would press well to the south.
In absence of snow, a quick freeze-up of wet areas from the central Appalachians to New England could lead to icy conditions.
In the wake of the storm, most of the Eastern states will be dry with seasonable temperatures to close out the week.