Fresh snow and erratic winds have created wind slabs on all aspects above 4,500' feet  On December 26th, we found these slabs to be reactive to human triggering on steep convex rolls and on slopes below saddles where the higher winds were funneling and depositing fresh snow onto leeward aspects.  These slabs were not highly reactive and were still quite soft.  We noticed that they increased in both cohesiveness and reactivity as the day progressed due to a steady pummeling from the wind.  These thin, soft slabs will likely become more reactive and dangerous with the predicted weather moving in on Tuesday, December 27.

Backcountry travelers should exercise caution when traveling through areas that are showing signs of recent wind loading.  Look for soft pillow like appearance in the snow. Signs of cracking and density changes in the snow should be taken as obvious clues that you may need to exercise extra caution and stick to low angle terrain that is  protected from the wind.  Avoid steep convex rolls as these slabs are proving to be very reactive on this type of terrain feature.

The mountains of the Kootenai National Forest are forecasted to recieve close to a foot of snow and strong westerly winds in the next 24 hours.    This scenario will likely create a substantial rise in the potential for both natural and human triggered avalanches.  Backcountry travelers can mitigate this hazard by sticking to low angle terrain (less than 30 degrees) until this new snow has had ample time to strengthen and settle.

The wind slabs of the previous two weeks have become less reactive with time and are now becoming buried within the snowpack.  We are not finding them to be reactive to human triggers or snow stability tests; however, they are worth paying attention to as additional loading is added to the snowpack.  These higher density layers are overlying a wide variety of weaknesses throughout the mountians of the Kootenai Region.  On northerly aspects we are finding buried surface hoar and faceting, depth hoar development in areas with a shallow snowpack, and old rain crusts lying underneath a layer of sugary facets at elevations above 6,500'.

As I mentioned these weaknesses are not proving to be reactive at this time.  This could change with addtional loading, a rapid rise in temperature, or a human trigger launching off a cornice on skis or a snowmobile.  This problem can be managed by assessing each slope individually before committing to it and practicing safe travel habits.