(CNN) - This has already been the snowiest February in Seattle and Tacoma in 70 years, and more snow is falling in the region Monday, according to the National Weather Service.
One to three inches of snow are expected to fall on the area throughout the day, before possibly giving way to freezing rain, rain or sleet, the weather service said.
"Snowfall accumulations may be heavier in the Seattle Metro Area and extend into the evening hours if the warm air moving in from the south arrives slower than expected," the weather service said.
A winter weather advisory remains in effect until 6 p.m. (9 p.m. ET).
"Expect snow-covered roads and limited visibilities, and use caution while driving," the weather service said.
Some areas around the Seattle area were covered in more than 10 inches of snow on Saturday, almost giving the city more snow in one day than it usually gets in a year.
Winter storm warnings have been issued for other areas, where heavy snow is expected Monday night into early Tuesday.
The areas are "the Strait, the northern interior, the mountains, the East Puget Sound Lowlands, and the interior from southern Snohomish County northward," forecasters say.
Snow will be particularly heavy around Bellingham, south Snohomish County and the East Puget Sound Lowlands.
The South Washington Cascades may see up to 36 inches of snow through Monday and into Tuesday morning, as a winter storm warning stays in effect, the weather service said.
There is a light at the end of the tunnel. By midweek, CNN meteorologist Pedram Javaheri said, it could get gradually warmer with a few sunbreaks possible.
But travel in western parts of the state could be "very difficult to impossible" Monday with snow covered roads and limited visibility, the National Weather Service said.
The Washington State Department of Transportation urged drivers to slow down late Sunday after a state patrol vehicle was hit and pushed into a second patrol vehicle on I-90 in the Spokane Valley.
A trooper was transported to the hospital with non life-threatening injuries, Trooper J. Sevigney, a spokesperson for the Washington State Patrol shared on Twitter.
Travel conditions have been hazardous in the state since Saturday. Blizzard conditions left hundreds of drivers stranded on a Washington highway over the weekend.
Gov. Jay Inslee, in declaring a state of emergency on Friday ahead of the winter storm, urged residents to "stay off the roads."
That warning continues as the weekend storm moves out, with local police departments urging drivers to stay inside on Monday unless they absolutely have to leave their homes.
The Seattle-Tacoma International Airport, where a record-breaking amount of snow fell over the weekend, is open.
But travelers are advised to check in with airlines for canceled flights and the airport warned that checkpoint waiting times may be longer.
More than 200 flights into or out of Seattle-Tacoma on Monday have been canceled.
Public schools across Seattle, Tacoma and Olympia have canceled classes on Monday. The state legislature said it also is taking the day off, canceling all scheduled committee hearings.
The King County Metro transit service will continue offering abbreviated service through Tuesday, using routes on roadways that have been plowed and treated for snow.
The Seattle Monorail said it would assess conditions to determine if and when it can open.