CNN  — 

Washington Gov. Jay Inslee declared a state of emergency Friday as the Pacific Northwest braces for a pounding snowfall, whipping winds and frigid air.

“Everyone in our state needs to focus on preparing for the snow and staying safe,” Washington Gov. Jay Inslee said in a statement. “I encourage everyone to stay off the roads if possible and plan ahead if you must travel.”

The huge Seattle metro region could get six to eight inches in its second snowstorm of the week, forecasters say.

“The snow is expected to start as early as noon today with heaviest snowfall expected late this afternoon into tonight before gradually tapering off throughout Saturday morning,” the National Weather Service said Friday.

CNN storm tracker

More than 12 million people in the Northwest are under winter weather alerts Large amounts of snow are expected on the north slopes of the Olympics, about eight inches and more. Some isolated areas could get a foot.

Parts of western Whatcom County may get an inch, but it could also experience blowing snow. The coast could see as much as three inches. Portland, Oregon, and the Sierras will be affected as well.

Seattle, which averages 6.8 inches of snow over the course of an entire year, is under a winter storm warning. If Seattle does reach the predicted six inches of snow, it will only be the fourth time the area has seen that much since 1991.

Authorities in the densely populated Seattle region are getting ready to tackle the storm.

Schools are closing and officials are warning drivers to lower their speed and pedestrians to take care. A road could be icy and dangerous in the low temperatures, even if it appears to be clear.

“It could be really challenging. Might start thinking about adjusting your weekend plans if possible,” the Washington Department of Transportation said in a statement. ” … If heavy snow is falling, there’s only so much we can do and it will affect roadways. Roads will be slick, bridges/ramps/overpasses will be icy, collisions will increase and traffic will be challenging.”

A lone car finds its way along an otherwise deserted street through snow and a cold wind Monday morning in Seattle.

With the declaration of a state of emergency, the Federal Motor Carrier Safety Administration is limiting the number of hours commercial vehicle drivers can be on the road. Only drivers collecting or delivering bulk milk products or de-icing road salt from that agency’s locations are exempt, the governor said.

Freezing temperatures and powerful winds

Temperatures are expected to remain below freezing until Monday afternoon, Brink said, with the forecast high expected to hit 35 degrees. Seattle’s average high at this time of year is 49 degrees, Brink said.

Temperatures are expected to remain below freezing until Monday afternoon, CNN’s Brink said, with the forecast high expected to hit 35 degrees F.

Those temperatures, combined with the wind, could make it feel like it’s in the teens Saturday across the Seattle region.

There’s a possibility of more snow for Seattle on Sunday into Monday.

Cancellations

The storm is affecting some planned activities, with a Friday appearance by Michelle Obama at the Tacoma Dome postponed to next month.

“With the snowstorm on its way into Tacoma, my biggest priority is making sure everyone stays safe – and that’s why we’ve decided to postpone my tour event to March 24th,” Obama tweeted. “I can’t wait to see you all next month, and in the meantime, stay warm and be safe out there!”

Several school districts in the Seattle metropolitan area are closing early Friday because of the threat of winter weather.

Seattle, Kent, Tacoma and Mercer Island are among the districts that have announced early release for students and faculty.

The University of Washington in Seattle said it is suspending operations at 12:30 p.m. (3:30 p.m. ET) Friday and all day Saturday. All classes and activities have been canceled.

The school is asking students and employees to “use caution when walking and driving on and around campus.”

The Tacoma and Bothell campuses have also announced suspension of operations starting Friday through the weekend.

Monday’s storm

Earlier this week, another storm shut down the city and left some neighborhoods with about half a foot of snow.

Seattle Public Schools first announced Monday that classes would start two hours late for its 53,000 students. “But as the snowfall increased, it was determined that roads were too challenging with ice and snow,” spokesman Tim Robinson said in an email.

More than 12,000 people were without power in Washington state due to snow-related outages.

The Department of Transportation said numerous spinouts were reported on interstates, and Interstate 5 through Seattle was shut down at times for snow removal and because of wrecks.

CNN’s Ralph Ellis, Haley Brink and Keith Allen contributed to this report.