Avalanche Forecast
Issued: Nov 20th, 2019 8:00AM
The alpine rating is Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeToday is the first day of the Winter Permit System. Ensure you have a permit to enter the restricted areas, provided they are open today.
A persistent slab has been surprising early season travelers the last few days. Choose conservative lines.
Summary
Weather Forecast
The ridge of high pressure has arrived. Sunny skies today with light N'ly winds and freezing levels rising to 1100m. Thurs brings sun with some clouds, light variable winds, and a weak temp inversion with alpine freezing levels reaching 2000m. Friday will see a mix of sun and clouds, light SW winds, and freezing levels near 1700m.
Snowpack Summary
A 35-50cm persistent slab sits on a crust/surface hoar/stellar layer. Below this are several melt-freeze crusts from late October. Tests are showing easy to moderate results on the persistent slab, indicating they are easily triggered by human loads.
Avalanche Summary
Human-triggered avalanches to size 2 were reported from Balu Pass Monday and the Asulkan Hut area over the weekend. The Balu Pass avalanche buried the person to their neck and gear was lost. Numerous natural avalanches to size 2.5-3 were observed from Tupper, Macdonald, and Cheops during the storm Sunday morning.
Confidence
Problems
Persistent Slabs
The persistent slab sits atop a crust/surface hoar/stellar layer, which is an ideal sliding layer for this avalanche problem. Cool temps will try to lock this slab in, but warm, direct sun may be a strong enough trigger to start an avalanche.
- Use caution in lee areas. Recent wind loading has created wind slabs.
- Minimize exposure to steep Southerly slopes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Nov 21st, 2019 8:00AM