The North Cascades Highway closed on Sunday from milepost 134 to milepost 171, due to heavy snowfall and high winds.
The highway closes every year during the winter. The state Department of Transportation will decide Tuesday whether to reopen the road or leave it closed.
Meanwhile, Stevens Pass on U.S. is covered with compact snow and ice. Chains are required for all vehicles except for those with all-wheel drive.
Check WSDOT for updates on mountain passes around the state.