Northwest Mountains

Avalanche hazards are minimal today due to a lack of recent snowfall.  They are rare, but stay alert for small instabilities in very steep or consequential terrain. The avalanche danger will rise overnight with the arrival of new and windblown snow favoring the Northwest Mountains.  

Our last storm was almost two weeks ago, and avalanche hazards are minimal.  If you are venturing into extreme or high consequence terrain on the northern half of the compass, stay alert for shallow sluffs and the rare chance for triggering a lingering slab from previous wind drifting events (Example A,  Example B).    It's great to see people taking advantage of our unusually quiet snowpack to chase big alpine terrain objectives.   Conditions will start to change overnight with a modest storm, and they should change significantly later this week with a much stronger system on Thursday and Friday.   

Our unusually dry November has caused our shallow snowpack to facet into a fragile weak layer of depth hoar and facets on the northern half of the compass.  Furthermore, surface hoar growth has been rampant on many below treeline and some higher elevation slopes.  It's a weak layer nightmare out there on shady aspects, and any newly forming slabs will be touchy right out of the gates.  The question isn't if, but when.   If our weather forecast verifies, expect some shallow slabs to form near and above treeline in the Northwest Mountains overnight, causing a localized bump in avalanche danger.  Snow totals look to fall short of this threshold in the Southeast Mountains.  If we get surprised by larger snow totals in either zone, the danger will notch up accordingly.  The stronger system on Thursday and Friday will likely bring dangerous conditions across the entire region.  Stay tuned and check out these weak layer observations from the Ruby Range and near and east of town.