THIS SNOWPACK SUMMARY EXPIRED ON February 17, 2017 @ 2:06 am
Snowpack Summary published on February 16, 2017 @ 9:06 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

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.