State Route 20 (SR 20) -- North Cascades Highway
The highway traverses the North Cascades, crossing Washington Pass which has an elevation of 5,477 feet and Rainy Pass which has an elevation of 4,875. Many people call this section of the North Cascades the "American Alps" and say the section of highway between Sedro-Wooley and Tonasket the most beautiful stretch of highway in Washington State. Snow capped craggy peaks, cascading waterfalls, glaciers, mountain top meadows, and views of Ross and Diablo Lake are a feast for the eyes. Words like "magnificent!" are used to describe the area.
Sections of Highway 20 are closed during winter months because of avalanches which can leave more than 20 feet of snow on the highway. The highway is closed at milepost 134, east of Diablo and at milepost 170, 14 miles west of Mazama. The highway west of Newhalem can be closed as early as November 25 and can stay closed up until late April. In the past 30 years, the highway was not closed during 1976-1977 because of drought conditions.
SR 20 traverses the following counties: Ferry, Island, Jefferson, Okanogan, Pend Oreille, Skagit, Stevens and the following cities and towns: Anacortes, Burlington, Colville, Newport, Okanogan, Omak, Port Townsend, Republic, Rockport, Sedro-Wooley, Tonasket, and Twisp.
With changing weather patterns in the winter, the Department of Transportation cannot guarantee when the highway will close. Besides checking the DOT web-site, travelers should take extra precautions during winter months including making sure they have a full gas tank, extra windshield wiper fluid, extra clothes, a shovel, extra food and water. Note that cell phone service is not available between Mazama and Diablo and in other areas of the highway.