Avalanche Forecast
Issued: Nov 25th, 2022 4:00PM
The alpine rating is Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeAreas where the snowpack is deep enough for winter recreation are the same places you'll need to factor avalanche danger into your trip plan. Wind loaded pockets at high elevations are the prime suspect right now.
Summary
Confidence
Moderate
Avalanche Summary
We don't yet have reports of avalanche activity from Friday's snowfall, but it's expected that small wind slabs would have been reactive to human triggering or even release naturally in steep terrain in the immediate lee of ridges or exposed terrain features during the storm. Where new slabs have formed, human triggering potential should persist through Saturday at least.
Please share your observations to the MIN!
Snowpack Summary
5-10 cm of new snow should arrive in the region by end of day Friday with timing that progresses from north to south. The new snow will add to a settling 15 to 20 cm of snow from Tuesday's storm.
The new and recent snow collectively overlies a variety of surfaces that formed mid-November, including weak surface hoar in sheltered treeline terrain, sugary faceted grains, a thin crust on steep solar aspects, or bare ground in wind-exposed terrain. In some areas this interface may present as a thin temperature crust that is more uniform across elevations and aspects.
Average snowfall depths are around 20 to 50 cm below treeline and 80 cm in the alpine.
Weather Summary
Friday night
Continuing flurries bringing up to 5 cm of new snow before easing in the evening. Light to moderate west winds.
Saturday
Mainly cloudy with isolated flurries bringing a further trace of new snow, increasing overnight. Light northwest winds. Treeline high temperatures around -4 C.
Sunday
A mix of sun and cloud with 5-10 cm of new snow from the overnight period. Moderate northwest winds easing over the day. Treeline high temperatures around -5 C.
Monday
Clear. Light northeast winds. Treeline high temperatures around -8 C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Wind slabs may be poorly bonded to the underlying crust.
- Carefully evaluate steep lines for wind slabs.
Problems
Wind Slabs
Recent light snowfall and southwest wind has likely formed small wind slabs in leeward terrain. Deeper deposits in the immediate lee of ridgecrests and exposed terrain features are the most suspect.
Avalanche hazard is unlikely anywhere snowpack depths have yet to overcome ground roughness like brush and rocks.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Nov 26th, 2022 4:00PM