MOUNTAIN WEATHER FORECAST

Stevens Pass Mountain Weather Forecast

Thursday, January 30, 2020, 1000

Current Observations:

24hr Precipitation:        .45 swe, 4” snow

Temperature profile:    27base,  31 ridge

Pass level winds:           light WSW

Barometer:                   bumped up to 1022mb’s

Sky:                               broken clouds

Radar:               dry conditions throughout the state.

The Forecast:  Snow turning to rain arrives late this afternoon with heavy rain and high winds expected through the night.   Windy and rainy conditions continue all day tomorrow.  

The Science:  The current temperature inversion is the indicator of the warm air streaming into the region from the southwest.  A strong warm front will charge in tonight with rising freezing levels and heavy precipitation expected.  The moisture source is a long SW fetch strung out well beyond Hawaii.  A fairly textbook pineapple express weather event.

The good news.  Cold unstable NW flow swoops in Saturday with some possible snow accumulation on the tail end of this inpressive storm.     

Long Range:  The rain turns to snow on Saturday with 6-8” possible heading into Sunday. Snow showers with falling temperatures are expected on Sunday and Monday.

Forecast confidence: Good.

Values from 4am today through 4am tomorrow.

Precipitation: Today 24hr water: 1-2”  snow: 1-2 Tomorrow’s 24hr water: 1-1.5  snow: 0 Trend and Timing: Snow will start sometime after 4pm and change to rain soon thereafter.  Rain is expected all day tomorrow.

Temperature: Low: 32  High: 42 Freezing level: 4500’ – 7000’ Trend and Timing:    Freezing levels will rise tonight peaking near 7000’during the day tomorrow.   Freezing levels are not expected to drop back down until sometime on Saturday.

Winds Base:  0-5 e shifting WSW and strengthening Ridge Top: 5-10 E shifting SW Trend and Timing: The winds will shift WSW with the passing of the front later today.  A high wind advisory will go into effect tonight and continue through morning hours.