November 23, 2018

MOUNTAIN WEATHER FORECAST


Stevens Pass Mountain Weather Forecast
Day and Time: Friday 0600

The Snapshot: The Puget Sound Convergence Zone came through last night with 14” of new snow. Snow showers will continue today and taper off tomorrow morning.   With temperatures hovering at or just below freezing it is good base making.
 
Current Observations:
Precipitation: It is lightly snowing.  .93” of water converts to 14” of snow,  11 of which fell since 4pm yesterday.  
Pass temperature: 31
Winds: 5-10 W
Barometer: 1005mb and slowly rising
Sky: Overcast and dark
Radar:  The radar shows a blob of moisture south of Everett moving NE into the mountains. 

The Forecast:  The snow will continue today and diminish overnight.  The weekend will be mostly dry with sun breaks. 

Long Range: The next push of moisture with rising freezing levels arrives on Monday.  The snow vs rain dynamic is still in question.  Light snow showers with dry periods will wrap up the week.   
  
The Science:  There are no defined warm or cold fronts approaching, just nice unstable westerly flow.  A strengthening high pressure ridge will shut off the moisture tomorrow and provide a 24-48hr dry period with partial clearing.  

Monday/Tuesday:  A large low pressure system with a strong SW fetch of moisture component will begin to move in on Monday.  East flow will develop as cool air from the weekend settles in the eastern basin.  Time will tell how the warm air advection mixes with the cooler east flow.  Stay tuned.

Values from 4am today through
 4am tomorrow.
Precipitation:
Today 24hr
water: .75+  snow: 8-10

Tomorrow’s 24hr
water:.10   snow: 1-2

Trend and Timing:
Snow ends just after 4am tomorrow.


Temperature:
Low: 28    High: 34
Freezing level: +3500’

Trend and Timing:   
Freezing levels will slowly fall to around 3500’ today and hold there through Sunday morning.

 
Winds
Base: 5-10 W
Ridge Top: 5-15 W

Trend and Timing:
Westerly flow will persist through early Sunday morning.  

No comments:

0800 Start Fri Jan 30th, no ABS