Winter weather conditions forecast across much of US

An ice storm is forecast to slam parts of Iowa and surrounding states.

Winter weather conditions are possible across much of the United States this weekend.

Winter storm warnings are in place for California's Sierra Nevada mountains until 10 p.m. Saturday, where 6 to 24 inches of snow are possible.

An avalanche watch is in effect for the backcountry areas in the Greater Lake Tahoe region due to the new snow and strong winds. This does not include ski areas and highways where avalanche mitigation programs exist.

Wind alerts are in effect for gusts up to 50 or even 60 mph on Saturday through much of California’s northern and central valleys.

Saturday evening, much of the rain part of this event will subside, but heavy snow will continue for Sierra Nevada overnight into Sunday.

Total snow accumulations up to 2 feet are possible in Sierra Nevada. One to 3 inches of rain are possible along the coast from the Bay Area to Oregon and Washington.

Mixed precipitation hits Midwest

The arctic blast is gone and warmer weather is leading to troublesome mixed precipitation in the Midwest.

A winter storm is bringing significant icing to parts of Iowa on Saturday, all thanks to freezing rain. The incoming warm air mass is one of the factors causing this ice storm, as rain falls on the sub-freezing ground in parts of Iowa, Nebraska, and Illinois.

Ice storm warnings were in effect until 3 p.m. Saturday in eastern Iowa where up to 0.30 inches of ice could weigh down trees and power lines leading to sporadic power outages, as well as icy roads.

Meanwhile, a winter weather advisory is in effect for surrounding states because a mixed precipitation will bring freezing rain, sleet and snow to the region as the system slowly pushes east Saturday.

Up to one inch of snow or sleet and a tenth of an inch of ice is possible for areas under the winter weather advisory.

By 5 p.m. CT, the mixed precipitation will be in northeast Iowa and southern Wisconsin, as widespread rain covers the state of Illinois down through Memphis and Nashville.

East Coast winter weather

Rain will reach Philadelphia and New York City on Saturday evening and snow will continue for northeastern Pennsylvania and upstate New York.

By Sunday evening, rain moves across the I-95 corridor, soaking cities like Philly, New York and Boston. Meanwhile in central and northern New England, snow and wintry mix could bring slick travel for commuters in the evening and overnight hours of Sunday.

On Monday morning, rain is still expected for New York City, but much of the snow to the north should be finished.