Winter storm to encase 1,700-mile stretch of US in ice, snow

A storm will serve as a reality check for millions of Americans this weekend, following a stretch of springlike warmth expected to challenge records. Wintry precipitation is forecast to overspread a 1,700-mile corridor of the United States, spanning from the Central to Northeastern regions.

The same storm system that will bring the threat for severe thunderstorms and flooding rain across the Mississippi and Ohio River valleys will also pose a threat for accumulating snow and ice beginning this weekend.

After the weather system tracks through the Northwest at midweek, it will intensify and tap into the available energy from an unusually warm and humid air mass surging out of the Gulf of Mexico.

A heavy rain threat will first expand across the mid-Mississippi Valley on Friday, then the threat for accumulating snow and ice will soon thereafter threaten portions of the Plains and Midwest while colder air seeps southeastward.

"The setup will result in a very tight weather contrast zone, where rainy conditions, snow and/or ice can all occur," AccuWeather Senior Meteorologist Alex Sosnowski said.

"Temperatures over this same 100-mile cross section can range from the balmy 50s and 60s F to the 20s and 30s," he added.

Beginning around the Friday evening commute, there may be a narrow corridor from northeastern Oklahoma, eastern Kansas into northern Missouri where atmospheric conditions allow for freezing rain to fall.

"Any roads left untreated, especially along the northern edge of this system, are likely to become covered in ice," AccuWeather Meteorologist Mary Gilbert said. "Even a glaze of ice on roadways may lead to increased spin-outs or even multi-vehicle accidents," she added.

Topeka, Kansas, as well as both Kansas City and St. Joseph, Missouri, could face this threat Friday afternoon and evening. Travelers along interstates 29, 35 and 70 in this area will want to monitor the forecast closely.

The threat for ice and snow will continue to expand northeastward into the Great Lakes Friday night into Saturday as the storm continues along its path.

Chicago and Detroit may face the threat for a wintry mixture of precipitation beginning Friday night.

The storm is expected to track eastward through the Ohio Valley on Saturday, and cold air filtering into the storm will gradually shift precipitation modes from ice to snow across the Midwest.

Some areas that may end up encased in ice may then see accumulating snow afterward, adding additional stress to tree limbs and power lines.

The storm will pivot and precipitation will transition to snow, burying portions of the Lower Peninsula of Michigan under totals in excess of 6 inches Saturday into Saturday night.

The snow and ice threat will continue to expand into the eastern Great Lakes as well as northern New England Saturday night into Sunday. Similar threats will exist across a corridor from western New York to Maine.

The threat for wintry precipitation could make travel treacherous across interstates 81, 87, 89, 90, 91, 93 and 95 across New York and New England over the latter half of the weekend.

"Exactly where the temperature and weather contrast zone ends up is key to the forecast," Sosnowski added. "The zone could shift farther to the north and west or perhaps farther to the south and east in the coming days."

The storm system will continue to track right off the Atlantic coast by the end of the weekend, bringing a return of dry weather early next week.

Download the free AccuWeather app to check the precipitation type expected and storm timing in your area. Keep checking back on AccuWeather.com and stay tuned to coverage on the AccuWeather Network.