Avalanche Forecast
Issued: Apr 9th, 2021 8:00AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Cornices.
Andrew Jones,
Wind and snow will increase avalanche hazard throughout the day. Cornices and glide cracks are springtime problems that are difficult to forecast for. Best to give both a wide berth.
Summary
Weather Forecast
A passing frontal system will bring flurries with 8cm of accumulation today and another 5cm overnight. Alpine temperature will reach a high of -6, SW winds 25km/h gusting to 65km/h, and freezing level at 1200m. A high pressure system establishes saturday afternoon, ushering in a spring like weather pattern for the next week or so.
Snowpack Summary
Up to 10cm of new snow is being blown into fresh wind slabs and covering a variety of old surfaces: settled powder on sheltered alpine N aspects, wind slabs/ wind pressed surfaces in exposed areas, a sun crust on solar aspects, and spring melt/freeze crust below treeline. Cornices are large and fragile. The March 18 crust is buried ~80-100cm.
Avalanche Summary
Two large glide releases (size 4 and size 3) were observed in the highway corridor off of Mt Tupper. A field team on Mt Fidelity was able to ski cut a size 1.5 wind slab at 2000m on a north aspect. The crew also observed a natural cornice fall resulting in a size 2 avalanche. The cornice did not trigger a slab.
Confidence
Problems
Wind Slabs
Strong southerly winds continue to whip recent storm snow into cohesive and reactive slabs in exposed areas near ridgelines and cross-loaded features. Today's forecasted snow and winds will exacerbate this problem and increase the hazard.
- Be cautious as you transition into wind affected terrain.
Aspects: North, North East, East, South East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Natural cornice failures have been observed over the past several days. Cornice problems are notoriously difficult to forecast for. Keeping distance between cornices and associated runout zones is good strategy for safe spring travel.
- Extra caution needed around cornices with current conditions.
Aspects: North, North East, East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 10th, 2021 8:00AM
