Avalanche Forecast
Regions: Glacier.
Early spring conditions call for careful evaluation of the snowpack throughout the day
Be mindful of overnight refreeze and how quickly it breaks down.
Confidence
Moderate
Avalanche Summary
Small loose wet cycle on steep sunny slopes Monday including one natural size 3.0 over a snowshed.
The March 27th crust has added strength to the snowpack but expect natural activity to pick back up during sunny periods or if freezing levels are higher than forecast.
A rain event caused a widespread natural avalanche cycle on Wed. Numerous very large wet avalanches ran down into the valley bottom. These avalanches included the deeply buried January Facets.
Snowpack Summary
10-20cm of surface snow is dry powder on northerly aspects in the alpine. On solar aspects there is a surface crust with up to 5cm new snow on top.
Surface snow sits on a 10-25cm thick crust of variable strength formed by the rain event March 25th. Field teams reported moderate compression test results within this crust.
Below 2300m moist snow can be found under this crust. If the March 27th persistent slab is triggered, it may entrain large wet loose avalanches.
Weather Summary
Unsettled conditions continue Wed
Tonight cloudy with clear periods, isolated flurries. Freezing Level (FZL) 1400m
Wed Cloudy with sunny periods. Alpine high -6°C. Wind W 20 km/h. FZL 1500m
Thurs Mix of sun and cloud, isolated flurries. Trace precip. Alpine high -6. Wind N 15. FZL 1600m
Fri Sunny with cloudy periods. Alpine high -4 °C. Light wind. FZL 1900m
Terrain and Travel Advice
- Back off slopes as the surface becomes moist or wet with rising temperatures.
- A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
- Overhead hazard may not be obvious; evaluate prior to commiting to terrain.
Avalanche Problems
Persistent Slabs
The March 25 rain event created a crust down 10-20cm. This persistent weak layer has variable strength & will become a problem if temps are higher then forecast or with strong solar warming.
Once this crust breaks down, moist snow trapped below the crust may entrain large wet loose avalanches
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 2.5
Loose Wet
Cloudy skies with sunny periods are forecast for Wednesday, however convective weather is unpredictable. Wet loose avalanches may be likely on solar aspects if the sun starts to heat things up more than expected. See travel advice.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2.5