At least eight persons were killed as heavy snowfall blanketed the US midwest Sunday, and airports on the east coast reported delays of an hour and more. In the upper midwest state of Wisconsin, eight people died in road accidents as motorists lost control of their cars in the severe driving conditions and swerved off the roadway, State Patrol Sergeant Nate Clarke told AFP.

"Three people were involved, a mother and two children, in a car that jumped over the center line and struck a county snow plow in Kenosha," where Clarke was stationed.

Wisconsin's largest city, Milwaukee, was hit with freezing rain and conditions could turn worse "if it gets colder tonight," Clarke said.

The storm dumped as much as 60 centimeters (24 inches) of snow on mountain states to the west on Saturday, and one motorist died in the blizzard, the Kansas Highway Patrol reported, when a tractor-trailer jackknifed while trying to brake and hit two cars stopped along the road.

The National Weather Service issued a blizzard warning for the southeast corner of Wisconsin and a winter storm warning for the rest of the state, as well as parts of Minnesota, Iowa and Michigan in the midwest.

A winter storm warning on the east coast meanwhile covered most of Pennsylvania, New Jersey, Maryland, Delaware, Virginia and part of West Virginia.

Washington, which was blanketed by several inches (centimeters) of wet, heavy snow and ice, declared a snow emergency at 2000 GMT.

Ronald Reagan National Airport and Washington Dulles International Airport outside the capital reported flight delays, and several flights were canceled as they tried to clear the runways.

While the Federal Aviation Administration reported no closed airports as of 2100 GMT, some had delays of an hour and more and flights were canceled.

Arrivals to Philadelphia International Airport, are delayed an average of an hour and a half, the FAA reported.

In Chicago's O'Hare International Airport, departures were delayed 15-45 minutes, as were arrivals, it reported.

Oddly, Wisconsin got less snow than it expected, Clarke said, and that may have contributed to the death toll.

He said even state patrol cars were pulled off highways, which are all still open.

"With our weather not falling into what was predicted," Clarke said, "We're getting a higher volume of traffic."