Avalanche Forecast
Issued: Apr 22nd, 2021 4:00PM
The alpine rating is
, the treeline rating is , and the below treeline rating isCool cloudy weather has made for generally safe avalanche conditions. Be careful around cornices and the isolated areas where the snowpack isn't capped by a thick crust.
Summary
Confidence
Moderate - Uncertainty is due to the limited number of field observations.
Weather Forecast
Thursday night: Partly cloudy with isolated flurries, light wind, alpine temperature near -8, freezing level valley bottom.
Friday: Mostly cloudy with isolated flurries, light wind, alpine high near -5, freezing level 1800 m.
Saturday: Flurries bringing up to 5 cm, light wind, alpine high near -5, freezing level 1600 m.
Sunday: Flurries bringing up to 5 cm, light wind, alpine high near -5, freezing level 1600 m.
Avalanche Summary
Warm temperatures last week resulted in widespread wet avalanche activity. The most notable activity was on Saturday where there was both widespread size 1-2 wet loose avalanches and a few larger and destructive (size 2.5-3.5) wet slab avalanches. The large wet slabs were mostly on south and west facing slopes. Avalanche activity has been on the decline since then with relatively cooler temperatures. A cornice fall triggered a large (size 3) slab avalanche on a north-facing alpine ridge in Glacier National Park on Tuesday.
The cooling trend will make wet avalanches problems unlikely in the coming days, making cornices the primary concern.
Snowpack Summary
The upper snowpack has undergone multiple melt-freeze cycles and is now crusty and refrozen in the cooler temperatures. Dry snow may still be found on northerly aspects above roughly 2300 m. There are no layers of concern in the snowpack, which has been melting and settling over the past week. Large cornices loom along many ridgelines.
Terrain and Travel
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
- Minimize your exposure time below cornices.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Valid until: Apr 23rd, 2021 4:00PM