Avalanche Forecast
Issued: Nov 27th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
JSmith,
Avalanche Canada
Forecast snow and wind will form LARGE touchy storm slabs at treeline and above. These slabs will be especially reactive on leeward features.
Careful route finding and conservative terrain use will be required to play safe in the mountains on Sunday.
Summary
Confidence
Weather Forecast
SATURDAY NIGHT: Snow/rain; 15-20 cm / Extreme, southwesterly winds / Low of -1 / Freezing level rising to 1300 m.
SUNDAY: Snow/rain; 5-15 cm / Extreme, southwesterly winds / High of -1 / Freezing level lowering to 900 m
MONDAY: Mix of sun and cloud with flurries / Moderate, southwesterly winds / High of -7 / Freezing level surface.
TUESDAY: Snow/rain; 10-20 cm / Extreme, southwesterly winds / High of -1 / Freezing level rising to 1200 m.
Avalanche Summary
Recent large, natural storm slab avalanches up to size 3 were reported on west and northwest aspects in the alpine.
Forecast snow and wind are expected to form touchy storm slabs at upper elevations that will be very reactive to human triggers.
Snowpack Summary
Forecast 15-20 cm of new snow and strong southwesterly winds will form reactive storm slabs sitting on a hard crust.
A crust formed in early November has been reported down 100-150 cm. There has been some evidence of large avalanches running on this crust. This will be a layer to monitor throughout the season.
Treeline snow depths are estimated to be 150-200 cm.
Terrain and Travel
- Avoid exposure to overhead avalanche terrain, avalanches may run surprisingly far.
- Avoid all avalanche terrain during periods of heavy snowfall.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Be especially cautious as you transition into wind affected terrain.
- Remember that the snowpack will be significantly different at higher elevations than lower down.
Problems
Storm Slabs
Forecast snow and wind will form LARGE touchy storm slabs at treeline and above. These slabs will be especially reactive on leeward features.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Nov 28th, 2021 4:00PM
