The state Department of Transportation is closing Chinook Pass on Washington 410 because of heavy snow and a possible avalanche hazard.
The pass was closed Wednesday evening, but it had not been determined if it would remain closed for the winter.
The closure runs from the Mount Rainier National Park boundary on the west to Morse Creek on the east, the department said.
The pass has received 15 inches of snow since Sunday, and forecasted warmer temperatures this weekend were expected to increase the danger of avalanche, the department said.
Chinook Pass, at 5,430 feet, usually is closed for the winter from mid-November to about Memorial Day.