The mountains of the Kootenai National Forest recieved two seperate shots of snow above 6,000' late last week. The most recent storm snow (top 6-8") is poorly bonded to the snow below. This new snow has the potential to release small storm slabs in steep terrain above 6,000' in elevation.
BOTTOM LINE: These storm slabs are not highly reactive or large and destructive. They should however be treated with caution in terrain where the consequences of getting knocked down are high. Avoid very steep, loaded gullies and terrain traps where a small avalanche has high potential consequences. The mountian weather forecast is also calling for more additional mountain snow which has the potential to exacerbate this problem.
New snow sits on last Saturdays rain crust. If it gets warm we can expect to see that snow come of the hill in a loose, sloppy mess. Continue to pay attention to changing conditions while riding and consider the potential consequences of being pushed down the hill in a small slide.
The last snowpack summary will be issued this coming Friday on March 31st.
My travels into the Eastern Cabinets this weekend revealed two layers of new snow resting on last weekends' rain crust. The upper layer (6-8' depending on elevation and loading) was poorly bonded to the snow below. It wasn't very reactive under foot; but, enough to make me shy away from skiing a steep chute off of a high ridge. We observed multiple glide cracks and older climax avalanches that likely released on bedrock during the March 18th rain storm. We observed no new avalanches on Sunday even though the sun was out and warming the upper snow pack.
Backcountry Forecast from NWS Missoula issued:
930 AM MDT Mon Mar 27 2017
DISCUSSION: Several inches of snow are possible above 5000 feet
today, mainly occurring over north central Idaho and far northwest
Montana ranges. A more significant chance for up to 6 inches snow
accumulation appears to arrive Wednesday to Thursday, with north
central Idaho and southwest Montana mountains most favored.
Outside of today and midweek, very light snow accumulations and
daytime temperature near or above freezing are anticipated.
--------------------------- 5000-7000 FT ----------------------------
Today Tonight Tue
Cloud Cover 95% 80% 85%
Hi/Lo Temps 33 to 42 23 to 30 33 to 42
Winds(mph) SW 13G24 SW 10G23 SW 8G20
Precip Chc 80 30 60
Precip Type sno/shr sno/shr sno/shr
Liquid Amt 0.13 0.02 0.06
Snow Amt(in) 1-3 0 0-1
Snow Level 4500 4000 3500
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.