Avalanche Forecast
Issued: Jan 20th, 2020 6:08PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
Deryl Kelly,
Parks Canada
Significant wind effect and cornice growth observed in the region, but no natural activity.
Summary
Weather Forecast
The arctic front has now retreated to the far north of BC. An upper ridge is expected to pass through. Warm air continues to invade overtop and through the mountains. For more info: Avalanche Canada Mountain Weather Forecast
Snowpack Summary
Settled snow becoming more cohesive over previous surfaces, mostly facets. The upper snowpack has facetted and weakened; this is more pronounced in shallow HS areas where less than ~60cm. Inconsistent mid-pack bridging over the basal facets and DH. HS average at TL: ~135cm.
Avalanche Summary
Control work on the Icefields Parkway today produced soft slab to size 1.5 on low elevation targets. Significant warming at low elevations producing snowballs and pinwheels on solar aspects. A wet slab (size 2) released below treeline (1400m) and schmooed (definitely a technical term) onto the road at Medicine Lake late this afternoon.
Confidence
Freezing levels are uncertain on Friday
Problems
Wind Slabs
New wind slabs at ridgetop along with cornice growth.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
- Avoid lee and cross-loaded terrain near ridge crests.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Cold facetting has weakened of the snowpack and compromised the bridging strength. Potential for triggering these deeper layers could increase as temperatures warm.
- Avoid convexities or areas with a thin or variable snowpack.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 21st, 2020 4:00PM
