Mountain Weather Forecast

Stevens Pass Mountain Weather Forecast

Day and Time: Saturday 0645

Current Observations:

24hr Precipitation:   .2" water/3” snow

Pass temperature:   28 degrees

Pass level winds: Moderate, gusty on ridgetops

Barometer:  1012 steady

Sky: Overcast

Radar: Spotty showers in Puget Sound with a light convergence zone north of Highway 2

The Forecast: Light snow showers ending Saturday morning. Cool and calm with east winds developing Saturday afternoon, partly cloudy. Light snow beginning after midnight and continuing during the day Sunday. Sunday will be warmer with freezing levels at or above pass level. Cool east flow may keep the precipitation type as snow.   

Long Range:  Monday looks to bring another brief break in the active weather and will be partly cloudy with light passing snow showers. The next system to watch arrives on Tuesday, and has the potential for heavy rain at high freezing levels with strong winds. Extended models are inconsistent with exactly where the bulk of the moisture will be aimed during this atmospheric river event. Details should emerge in the next few days.

  

The Science: Last night’s cold front has swept through Western Washington, bringing about 5 hours of gusty winds (max in the 50’s) and light snow. Washington will be under a cool upper level airmass for the remainder of Saturday. Transitory high pressure means it will be a generally calm day. Another front arrives Sunday morning, which will elongate and weaken as it moves inland. Freezing levels will rise again, but pressure gradients should be such that east flow in the passes will be in place. With cold air established in the Columbia Basin, Stevens Pass will hopefully squeak through the day with all snow. The peak warming with this system should be Sunday afternoon, so if we are to see “mixed precip” that’s when it would occur.

Values from 4am today through

 4am tomorrow.

Precipitation: Today 24hr water: .25   snow: 1-3” Tomorrow’s 24hr water: .5   snow: 4-6” Trend and Timing: Light snow ending this morning, the remainder of Saturday should be dry. Light snow beginning after midnight.

Temperature: Low: 24    High: 30 Freezing level: 2500’ Trend and Timing:    Temperatures remain steady today and tonight.

Winds Base: W 10-15, then E 5-10 Ridge Top: W 20-30, then ESE 10-20 Trend and Timing: Winds should calm down this morning and midday before switching offshore (easterly) this afternoon and evening.

DV