A major winter storm system making its way across the central parts of the country prompted emergency declarations and created havoc on the roads.

Snow emergencies are in place for much of Iowa as road crews worked overnight to clear the roads after seeing nearly 10 inches of snow fall on parts of the region. The state government on Monday said several of its COVID-19 testing facilities would be closed because of the storm. Public schools are either closed Tuesday or limited to online classes because of a weather system that descended on the area the previous day.

A winter storm warning remains in place for much of Iowa through much of the morning.

“Travel is still not recommended in many areas,” the National Weather Service advised on Tuesday. ”Road conditions will be slow to improve today even after accumulating snowfall ends."

Taylor Nicolaisen , a meteorologist at the National Weather Service, told the Associated Press on Tuesday that as much as 15 inches of snow are possible. It’s been about 15 years since the region saw that much snow in a single 24-hour period.

"This is historic snow," Nicolaisen said from Nebraska.

That warning came one day after Omaha Mayor Jean Stothert issued a snow emergency declaration.

Travel across the region remains hazardous. The Nebraska State Patrol said from is account on Twitter that it came to the rescue of more than 300 motorists and responded to 28 crashes as of 9 p.m. local time Monday. Parts of the interstate highway system in the state were closed down because of the storm, the state patrol stated.

Further west, and Chicago is under multiple weather advisories, including a winter storm warning and a lakeshore flood warning, with waves as high as 10 feet possible along the Lake Michigan coastline. Because of the warmer weather, the heavy, wet snow falling on parts of Chicago could lead to widespread power outages, the weather service said.

Meteorologist Lee Carlaw told the Chicago Tribune that heavy snow would continue to blanket the area throughout the day.

“I wouldn’t be surprised if by the end of the day we hit 8 inches,” he said.

Blizzard conditions in Chicago MacKenzie Perkins builds a snowman in a park during blizzard conditions in Chicago, Feb. 1, 2015. Photo: REUTERS/Jim Young