11/19/2012 Stevens Pass Mountain Weather Forecast

General Discussion: 14” of new snow overnight brings the base total to around 24”and building. The approaching warm front, just now hitting the coast, will cause the freezing levels to rise to 5000’ today. And thus, rain will still be possible today. The good news is that the water tap will be shut off tonight thanks to some weak upper level ridging.

Long-term: A cold front will bring cooler temperatures and more fresh snow tomorrow and Wednesday. There will be a possibility of an additional 6-10” of snow by Wednesday if the temperatures stay in our favor.

Things get very unpredictable after Wednesday. Now models have a high pressure ridge building over the inter mountain west, which if true, will hamper the Thanksgiving systems. No use forecasting beyond Thursday until the models begin to agree.

24hr Accumulative Precipitation Totals Starting at Noon Today:
“Water by midnight= .5
“Of additional water by 4am=>.10
“Of additional water by 12pm= >.10

24hr (12pm-12pm) Inches of Water = + .5

24hr (12pm-12pm) Inches of Snow = 4-8” above 4500’ 2-4” below 4500’.

Trend and Timing:
We should get the forecasted 1.25” of water by noon today. Heavy precipitation will continue for the rest of the day. Little to no moisture is expected after 10pm tonight. The next wave of moisture will move in tomorrow afternoon with more wet snow and or rain below 4500’.

24hr Base Area Temperatures (F) Starting at Noon Today:
Low: 23 High: 36
Freezing level: 4000’ 5000’

Trend and Timing:
Freezing will continue their climb reaching 5000’ by noon today. Freezing levels will continue to oscillate between 4000’ and 5000’ through Wednesday morning.

24hr Winds Speed (mph)/Direction Starting at Noon Today
Base: 0-10 E shifting W
Ridge Top: 10-20 WSW

Trend and Timing:
Surface easterlies will slowly be overridden today as strong SW flow aloft enters the mountains. Surface easterly will come and go with the passing of the next systems.