Avalanche Forecast

Moderate - Timing or intensity of solar radiation is uncertain

SUNDAY: Sunny in the morning then clouding over in the afternoon, light south wind, alpine temperature around -5 C.MONDAY: Cloudy with sunny periods, light southwest wind, alpine temperature around -5 C.TUESDAY: Cloudy with sunny periods, light southwest wind, alpine temperature around -5 C.

On Friday, cornice control produced 2 cornice chunks on northeast alpine ridges. One triggered a size 1 slab and the other entrained some loose snow. A natural size 1 wind slab and cracking under skies was reported in the central part of the region. A few larger avalanches were reported midweek, including a natural size 3 avalanche on a northeast aspect at 2500 m, an explosive triggered avalanche that failed on the ground down 100 cm, and a natural size 4 deep persistent slab that failed on a broad ridge feature on south through north aspects.On Sunday, morning solar radiation is a potential trigger for cornice falls and deeper weak layers. Read the forecasters blog (here) for advice on how to manage this low probability, high consequence scenario and check out the accompanying photos (here). Also expect wind slabs in the lee of exposed terrain at higher elevations.

10-20 cm of new snow overlies a widespread crust below around 2100 m and higher on solar aspects. Alpine wind has recently been strong mainly from south through west aspects and has loaded leeward slopes in exposed terrain at treeline and in the alpine. Large cornices are also reported in the alpine and appear to be largest on northerly aspects. At lower elevations, there are a couple rain crusts in the upper snowpack. 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.