MOUNTAIN WEATHER FORECAST

Stevens Pass Mountain Weather Forecast

Day and Time: 0930 

The Snapshot:   Increasing clouds today with mixed rain and snow tomorrow with snow leading into weekend.   See 3-5 day snow accumulations below.

Current Observations:

Precipitation: 0  

Pass temperature: 28

Pass level winds:  5-10 E

Barometer:  1017mb’s and slowly falling

Sky:  high over cast clouds

Radar: Most of the state is dry with the approaching weather system still a few miles off shore.

The Forecast:  The first wave of precipitation is expected to reach the mountains early tomorrow morning.  Pass level temperatures will be at or just below freezing through most of the day tomorrow – thus expect mixed rain and snow below 4500’ with snow on the upper ridges.  There will be a short break in the moisture early Thursday morning with the next wave of precipitation arriving during the afternoon hours.  Snow showers will persist through Friday.

Long Range: Saturday will be mostly dry with the next storm poised to enter the region on Sunday and then another possible storm early next week.  Freezing levels will be at or below 4000’ through the Saturday. Freezing levels are expected to rise above 5000’ on Sunday and Monday with rain possible.    

  

The Science:  The northern jet stream will shift its focus to the northern tier of the US over the next few days.  This will set up the first winter storm cycle for the PNW.

Snow accumulations values:  

By:     4am Thursday -  3-5”

          4am Friday – 5-7

          4am Saturday – 3-5

          4am Sunday – 2-4

Totals – 10-12 base area, 15-20 upper mountains.     

 

Values from 4am today through

 4am tomorrow.

Precipitation: Today 24hr water: .10  snow: trace Tomorrow’s 24hr water: .5  snow: 3-5 Trend and Timing: Mixed rain will enter the mountains after 4am tomorrow morning.

Temperature: Low:  28  High: 38 Freezing level: 4000’ Trend and Timing:    Freezing level will hold around 4000’ with the aid of east flow.

Winds Base: 5-10 E Ridge Top: 5-10 E Trend and Timing: East flow will hold through tomorrow.  Wind will shift WNW early Thursday morning.