Snoqualmie Pass - Weather

Weather

Snoqualmie Pass as it climbs into the Cascades passes through a micro-climate characterized by considerable precipitation, and at times hazardous conditions for travelers. The annual rainfall is over 100 inches per year, snowfall is over 400 inches per year. The number of days with any measurable precipitation is 170 or more per year.

The rapidly changing conditions require special cautions, relayed to motorists via variable message displays along I-90. Depending on traction they may call for tire chains to be installed, usually on large trucks but occasionally on smaller vehicles as well. Chain-up areas are provided along the side of the Interstate to facilitate the placement of chains. The pass has been subjected to closures when weather conditions become extreme.

Along one stretch of I-90 is a snow shed over the west-bound lanes, constructed in 1950 (47°21′20.68″N 121°21′57.65″W / 47.3557444°N 121.3660139°W / 47.3557444; -121.3660139 (snowshed)) for US 10. The use of sheds (very rare on Interstates) is an admission that plowing cannot keep up with snowfall and avalanches. A recent proposal suggests replacing the shed with a bridge to allow snow to pass under the highway.

WSDOT maintains cameras at selected locations along the pass to monitor weather conditions. Some of these cameras can be viewed via the internet.

Read more about this topic:  Snoqualmie Pass

Famous quotes containing the word weather:

    “Every incident connected with the breaking up of the rivers and ponds and the settling of the weather is particularly interesting to us who live in a climate of so great extremes. When the warmer days come, they who dwell near the river hear the ice crack at night with a startling whoop as loud as artillery, as if its icy fetters were rent from end to end, and within a few days see it rapidly going out. So the alligator comes out of the mud with quakings of the earth.”
    —Henry David Thoreau (1817–1862)

    “To recover a buried treasure without having it disappear miraculously in the process, one must be entitled to it, and also be willing—really willing deep in his heart—to share it with the poor and helpless. Buried money, especially silver, gives off a bright glow which comes right up through the earth and can be seen as a dim light on nights when the weather is misty or there is a gentle rain.”
    —Administration in the State of Ariz, U.S. public relief program (1935-1943)

    “Family values are a little like family vacations—subject to changeable weather and remembered more fondly with the passage of time. Though it rained all week at the beach, it’s often the momentary rainbows that we remember.”
    —Leslie Dreyfous (20th century)