THIS SNOWPACK SUMMARY EXPIRED ON February 17, 2017 @ 1:06 amSnowpack Summary published on February 16, 2017 @ 8:06 am
Issued by
Ben Bernall - Kootenai National Forest
Avalanche Character 1: Wet Slab
Wet Slab avalanches occur when there is liquid water in the snowpack, and can release during the first few days of a warming period. Travel early in the day and avoid avalanche terrain when you see pinwheels, roller balls, loose wet avalanches, or during rain-on-snow events.
We are currently recieving lots of rain on snow at the upper elevation. This will cause the snowpack to become heavier and weaker. This scenario will greatly increase the likelihood of wet slab activity as deeply buried weak layers in the snowpack become reactive under these conditions.
Because it is currently pouring rain in the Kootenai Region it is unlikely that many folks are going to be out in the mountains. If you do decide to go out realize that this rapid change in temperatures and additional water weight will create very unstable conditions that may result in large avalanches. Travel in avalanche terrain is not recommended today!
Avalanche Character 2: Loose Wet
Loose Wet avalanches occur when water is running through the snowpack, and release at or below the trigger point. Avoid very steep slopes and terrain traps such as cliffs, gullies, or tree wells. Exit avalanche terrain when you see pinwheels, roller balls, a slushy surface, or during rain-on-snow events.
The upper elevations recently had 4-8" of loose snow overlying a firm rain crust. As this loose snow becomes warm and saturated we will begin to see many small wet slides. These slides may also be enough to trigger deeper weaknesses in the snowpack and stepdown creating the wet slab problem mentioned above.
Again, today is one of those days where it is best to avoid avalanche terrain or the mountains altogether.
Snowpack Discussion
Big thanks to Marlene Kelsch and Libby Middle High School for hosting last nights "Know Before You Go" avalanche awareness presentation. And another big thanks to those that came out to listen.
recent observations
Today (Thursday February 16th) I will not be going out due to road conditions. I will be out on Friday and posting my advisory by 8PM February 17th.
Check out the forecast for the Idaho Panhandle by clicking the link below for more information!
http://www.idahopanhandleavalanche.org/current-advisory.html
Weather and CURRENT CONDITIONS
weather summary
Backcountry Forecast from NWS Missoula issued:
820 AM MST Thu Feb 16 2017
DISCUSSION:
A surge of tropical moisture is making its way through the
Northern Rockies today causing widespread precipitation. Snow
levels will remain fairly high during the day then drop tonight as
a weak cold front moves through the region. The mountains across
north central Idaho into west central Montana will receive the
heaviest amount of moisture from this event. An active weather
pattern will persist over the Northern Rockies through at least
mid next week.
Kootenai:
--------------------------- 5000-7000 FT ----------------------------
Today Tonight Fri
Cloud Cover 100% 95% 80%
Hi/Lo Temps 36 to 39 24 to 30 32 to 36
Winds(mph) SW 14G29 SW 14G25 SW 9G23
Precip Chc 100 90 40
Precip Type sno/rain showers sno/shr
Liquid Amt 0.40 0.13 0.05
Snow Ratio(SLR) 11:1 15:1 17:1
Snow Amt(in) 0-5 1-3 0-1
Snow Level 6000 4500 3500
Disclaimer
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.
