Avalanche Forecast

Moderate - Forecast snowfall amounts are uncertain

Tonight and Sunday: Periods of snow. 5-10 cm tonight and 10-15 cm on Sunday (snow looks heaviest in the northern part of the region). The freezing level is around 600-900 m. Winds are moderate from the S-SW easing to light. Monday: Cloudy with flurries and clearing. The freezing level is around 500-700 m and winds are light from the SW. Tuesday: Mainly sunny. The freezing level remains near 500 m and winds are light and variable.

On Thursday, slab avalanches to size 3.5 were observed on a variety of aspects and elevations. These occurred in response to heavy storm loading from rain and snow. The mid-January surface hoar was the suspected culprit in many of these avalanches. Of note was a size 4 slab avalanche in Steep Creek in the Duffey Lake area. Moving forward, cooling will likely put a cap on persistent slab avalanche activity, except on higher elevation slopes in the north of the region where reactivity is expected to persist. Forecast wind and snow could create fresh touchy wind slabs in exposed lee and cross-loaded terrain this weekend.

Convective precipitation delivered variable new snow amounts to the region on Friday. In the south, as much as 40 cm of snow may have accumulated, while further north there may have only been 10-15 cm. This new snow likely rests on moist/wet snow or a hard rain crust depending on elevation. A storm earlier in the week created deep and dense storm slabs in high elevation terrain and cause substantial cornice growth. Where it still exists, the mid-January surface hoar layer is between 60 and 130 cm below the surface. The combination of heavy storm loading and warm temperatures has likely flushed out this weak layer in many areas; however, I would still exercise caution on higher elevation slopes in the north of the region where continued reactivity at this destructive interface is likely to persist.