Avalanche Forecast
Regions: Glacier.
The snowpack had a poor recovery from the recent rain event. Make conservative decisions and avoid overhead hazards while the snowpack heals.
Confidence
Moderate
Avalanche Summary
A rain event into the alpine caused a widespread natural avalanche cycle on Wed. Numerous large wet avalanches ran down into the valley bottom.
Since then, natural activity has slowed down but human triggering remains a concern.
Neighboring regions have reported serious incidents and very large avalanches.
Snowpack Summary
A few cm's of moist snow sits on a saturated snowpack where 30mm of rain percolated down 70cm. How well the wet snow will recover with weak overnight freezing is uncertain.
Due to the rain event, we have lost 37cm in the total height of snow at 1900m.
The March 5 PWL consists of a crust &/or surface hoar and is down 60-120cm. There is concern that wet avalanches will step down to this PWL and entrain snow at lower elevations.
Additional PWL's from Jan/Feb are now buried 140-190cm deep
Weather Summary
Bands of light precip with a clearing trend starting Sunday.
Tonight: Trace precip. Alpine low -5°C. SW wind 20km/hr. Freezing Level (FZL) 1600m
Sat: Cloudy w/ sunny periods & isolated. 4cm. Alpine high -4°C. West wind 15-25km/hr. FZL 1900m
Sun: Mix of sun & cloud. Trace precip. Alpine High -2°C. SE wind 10km/hr. FZL 2000m
Mon: Mix of sun & cloud. Trace precip. Alpine High 0°C. SE wind 10-20km/hr. FZL 2000m
Terrain and Travel Advice
- Triggering deep layers is more likely if the snow surface didn't freeze overnight.
- Wet avalanche activity may step down to deeply buried persistent weak layers at lower elevations.
Avalanche Problems
Storm Slabs
Flurries are accumulating in the alpine & treeline with moderate wind transport. Use caution in leeward terrain features.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 1.5
Persistent Slabs
A persistent weak layer (PWL), buried March 5th, is down 60-120cm. Depending on aspect and elevation, this layer may be suncrust, facets &/or surface hoar. New avalanches may step down to this layer resulting in large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Unlikely
Expected Size: 2.5 - 4
Loose Wet
It is uncertain how well the snowpack will recover from the recent warming & rain. If there is a poor freeze overnight, expect wet loose avalanches to still be of concern.
Aspects: All aspects.
Elevations: Below Treeline.
Likelihood: Possible
Expected Size: 1.5 - 2.5