State Route 20, or the North Cascades Highway, in Whatcom County will close to vehicles Wednesday until the spring due to winter weather conditions.
SR 20 will close to traffic between Diablo and Mazama on Dec. 11 at 6 a.m., according to the Washington Department of Transportation. This is the latest closure date for SR 20 since 2008 when the pass remained open until Dec. 15.
SR 20 is the northernmost route across the Cascade Mountain Range in Washington. It's also part of the Cascade Loop, which is a 400-mile driving tour through the Cascades, according to WSDOT.
WSDOT said crews close this stretch of SR 20 ever year once snow fills the avalanche chutes that line the highway, which poses a safety risk to travelers and road crews.
The road closure points are at milepost 134/Ross Dam Trailhead and at milepost 171/Silver Star Gate. WSDOT says when snow begins to fall, crews will move the western closure point back to milepost 130/Colonial Creed Campground and the eastern point to milepost 177/Early Winters Campground.
Hikers, skiers, snowmobilers and other winter recreationists can access the closed portion of the highway during the winter season by parking in designated areas and allowing plow drivers to clear the snow.
WSDOT recommends checking the forecast and road conditions before you go, as conditions can change quickly in the mountains.
SR 20 usually reopens in the spring by early May.
