Snowstorm to march through interior Northeast dumping up to 18 inches

A winter storm that AccuWeather forecasters say will impact 100 million people in the United States is set to bear down on the Northeast during the latter part of the Martin Luther King Jr. holiday weekend.

The storm will strike the Appalachians in a fast and furious nature, leaving many areas buried under more than a foot of immobilizing snow. Even for major cities along the Interstate 95 corridor of the Northeast, a quick dose of snow followed by heavy rain and strong winds could pose travel problems.

"We're gearing up for an active weekend," AccuWeather senior on-air meteorologist Michelle Rotella said. Winter storm watches were issued across several states in the East on Friday ahead of the storm.

After dumping heavy snow on parts of the Plains and Midwest, the storm system will take aim at the Tennessee Valley and the Southeast with snow and a dangerous ice storm. Then, the storm will make an unusual U-curve turn and race north-northeastward up the Atlantic Seaboard Sunday evening to Monday, with the heaviest snow expected to come down quickly along the spine of the Appalachians.

Along the I-95 corridor, where the center of the storm is likely to track, warm air is forecast to be drawn in from the Atlantic Ocean, which will cause rain to fall during most of the storm. But, even the major cities of Washington, Baltimore, Philadelphia, New York City and Boston have the potential to be hit with a brief dose of snow or a wintry mix on Sunday night.

The wintry precipitation can rapidly cover roads and make for slippery travel at the onset of the storm before any accumulation is washed away by rain in these places as the night progresses.

From that stretch of the I-95 corridor to the beaches, several hours of heavy rain and strong winds could trigger urban flooding and sporadic power outages.

On the barrier islands and along the shores of some of the back bays, minor to moderate coastal flooding is likely due to the storm's easterly winds and the astronomical effects of the approaching full moon on Monday. Gusts will frequently reach 40-60 mph along the coast. Some thunderstorms may even rumble along the coast.

Farther inland, the northern and western suburbs of the I-95 cities will lie within a battle zone between warm and cold air associated with the storm. Heavy snow will transition to sleet, freezing rain and rain in areas north and west of Washington, to New York City and Boston, according to AccuWeather chief on-air meteorologist Bernie Rayno.

Travel over the zone from 25 miles to 75 miles northwest of I-95 from northern Virginia and central Maryland to Massachusetts and New Hampshire will be a mess. Roads could turn from snow-covered to slushy and icy in some areas, AccuWeather forecasters warn.

Motorists in southeastern Pennsylvania, northwestern New Jersey, the lower Hudson Valley of New York state and central New England could all face the sloppy to dangerous travel conditions.

Areas farther to the west will be in the heart of the snowstorm, which won't reach the intensity or output of one of yesteryear's most infamous winter storms. The storm's intensity, fast movement and a sweep of dry air may prevent a repeat of the blizzard of '93, which unleashed a widespread 2-3 feet of snow, high winds and mountainous drifts in the Appalachians.

Still, at the height of this storm from Sunday night to Monday, travel may be extremely difficult to impossible in the region. Thundersnow could accompany this snowstorm as an indication of its formidable strength.

"The storm will move swiftly northeastward with the heaviest snow lasting only about six hours and most of the snowfall spanning about 12 hours," AccuWeather senior meteorologist Bill Deger said. However, the intense rate of snowfall will make up for its short duration.

In the heart of the snowstorm, travel along major highways in the area, including along Interstates 81, 87 and 99 that run along the spine of the Appalachians, as well as interstates that pass from west to east through the mountain chain, could be shut down.

Over the Appalachians, snow will fall at the rate of 1-3 inches per hour with blowing and drifting snow that can reduce the visibility to near zero at times and may make it difficult for road crews to keep up. Motorists that plan on traveling along portions of Interstates 64, 68, 70, 76, 77, 80, 86, 90 and others will run into the heavy snow and the potential for treacherous conditions.

AccuWeather is projecting a broad area of 6-12 inches of snow accumulations throughout the Appalachians, and even into portions of Ohio, western New York state and the St. Lawrence Valley along the United States-Canada border. Within this zone, bands of 12-18 inches of snow will occur. Snow totals approaching 3 feet or more are most likely over the ridges and peaks of the Appalachians, Adirondacks and Green and White mountains.

Pittsburgh, Johnstown and Scranton, Pa.; Buffalo, Binghamton, Albany and Syracuse, N.Y.; Morgantown, W.Va.; Cleveland and Pittsfield, Mass.; Burlington, Vt.; and Caribou, Maine, all face substantial snowfall from the storm.

"Heavy snow is also forecast to fall all the way to much of the Maine coast, where the surge of warm air is likely to get pinched off," Deger said.

The blast of wintry weather will end as quickly as it arrives. Snow will quickly wind down from southwest to northeast spanning Monday morning to Monday night. Some blowing and drifting of snow will continue to occur in the wake of the storm, but after that, conditions should be favorable for crews to begin clearing roads.

Just as a fresh injection of cold air will help set the stage for the major winter storm, cold air will rush in the wake of the system on Monday night. Any wet and slushy areas will freeze, leaving untreated roads, sidewalks and parking lots slippery and dangerous. Temperatures are forecast to dip into the single digits across the northern tier of the Northeast to the teens and lower 20s over much of the Ohio Valley and central Appalachians to the upper 20s along I-95.