Warm air troughs have been bringing repeated waves of rain to the Washington Cascades for the past week, with occasional dips in the freezing level which resulted (mostly) in freezing rain in or near the passes. The cold air sitting over British Columbia finally began to push southward late Thursday, resulting in heavy snow in the Mt. Baker area and as far south as Stevens Pass.
According to the Northwest Weather and Avalanche Center (NWAC), the avalanche danger is rated as High above 5000 feet, moderate at lower elevations. The snowpack will likely stabilize somewhat over the weekend due to an increase in high pressure and decreasing orographic shower activity. Combine this with the encroachment of Joe Public into the alpine regions (at least into the inbounds and sidecountry regions) and we should see the danger decrease by Monday.
High winds scuttled the upper mountain areas of Crystal Mountain today, forcing the closure of High Campbell and Northway, along with wind-hold status for Rex and Green Valley. Further north at Stevens Pass and Mt. Baker, my onsite crew reported steady rain below 4000 feet and sloppy, Cascade concrete conditions above the snowline.
It seems the NWAC is reluctant to make a definitive prediction for the period from Sunday through Tuesday but the current indications call for increasing westerly flow to bring cooler air, along with showery conditions in the passes. Snow levels should be low enough to produce snow in most alpine elevations. More to come as the weekend progresses.
