So, in case you haven't heard. Winter is still here and about to give us another shot of heavy mountain snows begining Thursday night and rolling into Friday. This additional rapid loading combined with the high forecasted winds will likely create dangerous avalanche conditions this weekend.
BOTTOM LINE: Avalanche stability decreases rapidly with rapid changes in weath
Backcountry Forecast from NWS Missoula issued:
220 PM MST Thu Mar 9 2017
DISCUSSION: Widespread light snow down to 1500 feet this morning
will slowly rise throughout today, particularly for all ranges
south of I-90.
Significant heavy snow remains in the forecast for northwest
Montana ranges, particularly in the vicinity of Glacier Park, this
evening through Friday. An arctic airmass will move west of the
Continental Divide today and stall along the Canada border today.
The stalled edge of the arctic air will be a focal point for
periods of intense snowfall. Up to 2 feet accumulation is expected
along the Continental Divide. The arctic air will slowly retreat
east late tonight, with snow levels and snow density increasing
over time (i.e., upside down snow pack). Wind will also be a
factor right along the Continental Divide, where east winds
gusting to 30 mph will transport fresh snow to west facing slopes.
Large fluctuations in temperatures will add to dangerously
variable backcountry travel conditions.
Conditions for backcountry travel improve this weekend with high
pressure overhead, however it is not necessarily a dry forecast.
Snow levels will increase substantially through the weekend,
reaching 5000 feet at times. Additional storm systems will bring
more snow, mostly above 5000 feet, through the next week. Mountain
snow pack will continue to steadily increase.
--------------------------- 5000-7000 FT ----------------------------
Tonight Fri Fri Night Sat
Cloud Cover 95% 90% 75% 80%
Hi/Lo Temps 21 to 30 34 to 39 22 to 27 32 to 38
Winds(mph) SW 11G31 SW 21G47 SW 13G33 S 7
Precip Chc 100 100 30 40
Precip Type snow snow snow snow
Liquid Amt 0.77 0.49 0.01 0.05
Snow Amt(in) 9-11 5-8 0 0-1
Snow Level 1000 3000 4500 3000
This advisory applies only to backcountry areas outside established ski area boundaries. This advisory describes general avalanche conditions and local variations always occur. This advisory expires midnight on the posted day unless otherwise noted. The information in this advisory is provided by the USDA Forest Service who is solely responsible for its content.