(CNN) - Seattle got almost the same amount of snow it gets in a year in one day, leaving officials scrambling to get people off the streets and Washington's governor declaring a state of emergency.
Seattle-Tacoma International Airport had 6.4 inches of snow Friday, according to the National Weather Service. It's the second most snow recorded in the area in a day for the past 20 years, and more is still to come.
By 4 a.m. PT Saturday, the airport had 7.2 inches of snow, and it was still falling.
It's only the fourth time the area has seen 6 inches of snow since 1991. Seattle averages 6.8 inches of snow over the course of an entire year.
CNN storm tracker
Further inland, some areas of Washington state are reporting 12 to 18 inches of snowfall.
More than 15 million people across the Western US are under winter storm alerts Saturday morning, according to CNN meteorologist Haley Brink.
Washington takes precautions
More snowfall is expected Saturday, and officials are prepared. Washington Gov. Jay Inslee declared a state of emergency Friday as the region braces for whiteout conditions, whipping winds and frigid air.
"Everyone in our state needs to focus on preparing for the snow and staying safe," Inslee said in a statement. "Weather forecasters predict this may be a storm unlike one we've seen in many years. I encourage everyone to stay off the roads if possible and plan ahead if you must travel."
Seattle police tweeted that additional resources have been dedicated to getting the homeless community into warm shelters.
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.
Those stuck at home are taking a lighter tone to the Seattle area's predicament.
Mike Jacobs tweeted that since supermarkets were out of kale thanks to "tiny fluffy balls of icy death," he was going to stay home and guard his supply.
Freezing temperatures and powerful winds
The winds expected to accompany the storm could cause issues with blowing snow as well as downed power lines and trees. Wind gusts could reach anywhere from 20 to 30 mph in the Seattle area, while the northern Puget Sound and Olympic region could see gusts of 60 mph.
Temperatures are expected to remain below freezing until Monday afternoon, CNN's Brink said, with the forecast high expected to hit 35 degrees F.
Seattle's average high at this time of year is 49 degrees, Brink said.
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.
Earlier this week, another storm shut down the city and left some neighborhoods with about half a foot of snow.