Avalanche Forecast

Fair - Intensity of incoming weather is uncertain

Unstable conditions expected through the weekend. Two cold fronts back to back, will bring light to moderate snow amounts, accompanied by a strong upper SW flow. The Western ranges may see higher snow amounts. The second frontal system looks to be a bit punchier. Friday: Dry in the am. Snow amounts 5-15 cm. Snow continued overnight. Ridgetop winds moderate from the SW. Treeline temperatures near -6. Freezing levels 1200-1400 m. Saturday: Snow amounts 10-20 cm. Ridgetop winds moderate-strong from the SW. Freezing levels 1000-1400 m. Sunday: Light-moderate snow amounts as the front moves through. Freezing levels should drop to 1000 m by Sunday night into Monday.

On Wednesday operators did full explosive testing and reported numerous large avalanches. This may indicate the triggering potential that lies ahead. The snowpack is susceptible to new storm slab, wind slabs, cornice fall, sled and skier triggers. The scary fact is the avalanche size. Even a small avalanche could step down and trigger a persistent weak layer, which in turn will create a large, destructive avalanche. Remote triggered avalanches (from afar) are still being reported up to size 2.5. Many skier triggered size 1-2 avalanches have also been reported. Monday/Tuesday the region saw a widespread natural avalanche cycle in response to snow, wind and warming. With more snow and wind in the forecast the avalanche danger will elevate.

The weekend past, up to 80 cm of storm snow fell. Strong winds from the SW and fluctuating temperatures were the perfect recipe for storm slab, and wind slab instabilities. A 80-170cm thick slab sits on variable old surfaces (surface hoar, facets, and crusts) that formed mid-February. These persistent weak layers have remained touchy all week and are a key concern at all elevations. Easy-Hard test results, with sudden planar shears have been reported on the weak layer. If triggered, the avalanches will be larger than expected. There may even be step-down potential on deeply buried weak layers. Large cornices have formed and loom as potential triggers on the slopes below.