Mountain Weather Forecast

Weather Synopsis

A warm front continues to slowly lift north over our area, plowing a steady stream of moisture over the area with a focus on the Mt Hood area and the south and central WA Cascades on both sides of the crest.  Strong high pressure anchored inland and the center of low pressure system offshore continues to draw a steady tap of very cold air from eastern WA and through the Passes. The western boundary of the cold air will continue to erode over the next 24 hours as SW flow pumping milder air in aloft.  

This should make for a messy precipitation-type forecast tonight and Friday for many areas near the Cascade crest. Look for localized freezing rain tonight for the Mt Hood area, most likely for middle and lower elevations along with heavy precipitation through the evening and varying wind directions. For the WA Cascades, the western foothills are likely to see freezing rain with heavy snow closer to the Pass and on the east side. As warm frontal precipitation lifts north over the area and ends tomorrow morning, that's the most likely time to see a period of light icing for White and Snoqualmie Pass, and along the east slopes of the Cascades south of I-90. Stevens Pass and along the east slopes of the Cascades north of I-90, this will most likely be an all-snow event all high uncertainty remains. Moderate to locally strong S-SE winds will continue overnight as well. 

As the frontal feature hangs up over the Olympics and northwest Cascades late tonight through Friday, we should see a more straight forward warm-up and a switch from snow to rain at mid-elevations. 

We should temporarily dry out Friday night and Saturday. The exception would be a chance of showers rotating up from the south over the Olympic peninsula. Temperatures will continue to moderate over the region. Temperature inversions will be commonplace near the Passes; look for cold air and low clouds in the Passes and milder air at mid or upper slopes.