Avalanche Forecast

Moderate - Forecast snowfall amounts are uncertain on Wednesday

A series of low pressure systems will sweep across the Interior tonight through tomorrow bringing precipitation and light-moderate winds. A clearing trend with an associated ridge will start to set up later Thursday into Friday. Wednesday: Snow amounts 5-10 cm. Ridgetop winds will be moderate from the West and freezing levels near 1700 m. Thursday: Mostly cloudy with isolated flurries and some sunny breaks. Ridgetop winds light-moderate from the NW. Alpine temperatures near -3 and freezing levels 2000 m. Friday: Sunny with some high cloud. Alpine temperatures high of -2 and freezing levels 2000 m.

On Monday, a natural cornice fall was observed from a West aspect size 2.5. Several explosive controlled cornices also produced size 1.5-2 avalanches but not triggering deeper weak layers or very large avalanches from the slopes below. With continued precipitation, warming and wind, natural avalanche activity may continue, however; rider triggering is likely. Fragile cornices are also suspect, they are large enough and act as heavy triggers for deeper slab avalanches to release on the slopes below. If you're traveling below treeline where the avalanche hazard is lower than it is in the alpine you should remain diligent with your terrain use, mitigate overhead hazards by avoiding or lingering in run-out zones where large avalanches could come down from above. We remain in a low probability, high consequence scenario for persistent slab avalanches failing on deeply buried weak layers. Check out the recent Forecaster Blogs for more details.

Up to 10 cm of recent snow has fallen at upper elevations and caps a sun crust on solar aspects. This brings 20-40 cm of accumulated snow over the past week. This recent snow overlies a widespread crust below 2300 m and higher on solar aspects. Alpine wind has recently been strong mainly from the SW and has loaded leeward slopes in exposed terrain at treeline and in the alpine. Large, fragile cornices also exist along ridgelines. At lower elevations, there may be multiple crust layers in the upper snowpack which are now generally well bonded. At higher elevations, the February crust/facet layer is now down around 90-150 cm and has been reactive with several avalanches recently releasing on it. It is expected to be most reactive in the alpine where the snowpack remains dry. The deep mid-December facet layer and November rain crust both still linger near the bottom of the snowpack and a few avalanches and cornice falls have stepped down to these layers recently resulting in very large avalanches.