Early outlook: How will weather leading up to Christmas affect travel, white Christmas chances?

Large storms and cold air are likely to take a break over much of the nation during much of the week ahead of the Christmas holiday.

Generally quiet weather conditions can be expected over the Lower 48 states from Monday, Dec. 17, into Wednesday, Dec. 19.

The only exception to the quiet weather pattern during this time will be in the Northwest corner of the nation, where storms will continue to roll ashore.

Blustery and cold conditions are forecast to follow the departing storm in the Northeast with bands of lake-effect snow likely off of Lake Erie and Lake Ontario during Monday and Monday night. Steady, accumulating snow can also fall in Maine during this time.

Travel during this holiday season is likely to be the heaviest on record, according to the American Automobile Association (AAA).

More than 102 million people will take their vehicle on a holiday trip, and congestion could be four times that of a normal trip around some of the major cities with some of the worst days for travel expected to be on Wednesday, Dec. 19, and Thursday, Dec. 20, AAA stated in their press release. These days will bring a mix of commuters heading to work and the beginning surge of holiday travel.

Toward the end of the week, a pair of storms may converge on the eastern half of the nation.

"One storm may spring up from the South with a chance of rain spreading from the Gulf of Mexico to the Ohio Valley and Northeast," according to AccuWeather Lead Long-Range Meteorologist Paul Pastelok.

Depending on the strength and extent of that storm later in the week, there may be added slowdowns on the highways, a greater risk of accidents and perhaps some minor airline delays related to poor visibility and a low cloud ceiling at some of the major hubs in the East.

"If an Alberta Clipper catches up with the storm and allows cold air to plunge on its backside, there is the potential for either snow or a changeover to snow in the Midwest," according to AccuWeather Senior Meteorologist Kristina Pydynowski. "That can definitely foil up travel plans and could lead to delays in the arrival of holiday shipments."

"If another storm follows on the heels of the late-week system, there can be a narrow stripe of snow from the Midwest to New England the day or two before Christmas," she added.

The weather pattern may stay ornery with the potential for a big storm in the eastern part of the nation perhaps shortly after Christmas.

"We believe there will be some sort of potent storm that brews near the Gulf of Mexico just prior to Christmas with a window of movement from straight off the southern Atlantic coast to the Great Lakes during Christmas Day or as late as Thursday, Dec. 27," Pastelok said.

Both of the storms, late next week and after Christmas, may fuel heavy thunderstorms in part of the Deep South.

Meanwhile, there may be a gusty wind event for California by next weekend, followed by patches of snow and cold air that spread southward over the interior West during the week of Christmas.

The timing of the storms in the East and the West will ultimately determine which areas of the nation end up with a white Christmas.

Officially, a white Christmas is determined by at least an inch of snow on the ground and not necessarily snow falling on the holiday.

This map shows the probability of a white Christmas (1 inches of snow on the ground or greater), based on climatology and not anticipated conditions for Dec. 25, 2018.

The 1-3 feet of snow that fell on the southern Appalachians and Piedmont areas from last weekend will have melted long before Christmas.

Best bets for a white Christmas in 2018 will be over ski country in the Rockies, Sierra Nevada, Cascades, the northern Great Lakes and the northern Appalachians.

"There may also still be snow on the ground on Christmas Day from the late-week storm or the other on its heels in parts of the Midwest, central Appalachians and New England," according to Pydynowski.

AccuWeather will continue to provide updates on travel weather for the days leading up to and through the Christmas holiday. Download the AccuWeather app to see the forecast for your area.

TradeWx offers protection against financial risks of snow accumulation and other weather events. Learn more on TradeWx.com.