November 6, 2013

MOUNATAIN WEATHER FORECAST



Time: 11:30
 

The Snapshot: Snow changing to rain and then back to snow starting tonight and lasting through Friday morning.  Drier conditions develop on Friday and continue through the weekend.


Atmospheric Science:  A low pressure system approaching the PNW coast today will bring another round of precipitation to the mountains tonight and tomorrow.  Warm SW air will accompany the front tonight rising freezing levels,  A cold front will quickly follow tomorrow with cool NW flow filling in and lowering freezing levels to around 4000’.  East flow will play a part in the general temper pattern.    


4-7day Long Range:  Another system slides down the coast over the weekend but does not appear to make it to the mountains.  Therefore, light scattered snow showers with sun breaks can be expected for the weekend and early next week.  Warm southerly flow is expected to bring high freezing levels (6000+) during the first half of next week.  



 
24hr Accumulative Precipitation Totals Starting at Noon Today:
 
Water by 4am = .5 Snow equivalent = 1-3
 
Total inches of water by noon tomorrow = .75+
Total inches of snow by noon tomorrow = 2-5”
 
Trend and Timing:
Snow will begin to appear late this afternoon.  Snow is expected to change to rain tomorrow morning.   Rain will switch back to snow tomorrow afternoon with the passing of the cold front.  An additional 4-8” can be expected by Friday morning.
 
 
24hr Base Area Temperatures (F) Starting at Noon Today: 
                                     
Low: 30   High: 40
Freezing level: 4000’      5000’ 
 
Trend and Timing:   
Freezing levels will rise to 5000’ after midnight tonight.  Temperatures will then slowly decline through the day tomorrow with freezing temperatures hovering near or just above Pass level.  
 
 
24hr Winds Speed (mph)/Direction Starting at Noon Today:
 
Base: 0-5 E  shifting WSW
Ridge Top: 5-10 E shifting W
 
Trend and Timing:
East flow will hold through the night and shift westerly tomorrow afternoon.   Strong gusty winds can be anticipated tomorrow afternoon and evening with 40+mph gust possible.
 

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0800 Start Tues Jan 20th, no ABS