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.

This morning, heavy rain is falling across San Francisco up to Sacramento – rainfall rates of 1 inch per hour are possible.

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 quarter-inch of ice is possible Saturday morning in eastern Iowa as an ice storm slams the region.

Ice storm warnings are 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

By Sunday afternoon, snow will be falling in central Pennsylvania and western New York, with rain reaching Washington, D.C., by midday too.

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

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