Avalanche Forecast
Issued: Feb 13th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
AB,
Avalanche Canada
Keep isolated wind slabs in mind in the alpine, and also remember that triggering a persistent slab is not outside the realm of possibility. Steep thin snowpack areas seem particularly suspect.
Summary
Confidence
Avalanche Summary
A size 2 and 2.5 skier-triggered deep persistent slab in the Cirque Forepeak area occurred Tuesday showing that the persistent layers can still be triggered in thin snowpack areas.
Lake Louise patrol reported triggering very small and thin wind slabs in high alpine lee areas with ski cuts.
Sunshine Patrol reported triggering soft slabs 5-10cm thick with ski cuts in the alpine.
No avalanches were observed by the field on Mt. Whymper today.
Snowpack Summary
10-25 cm of recent storm snow sits over the Feb 3 crust. Isolated wind slabs are present in alpine lee areas. The Feb 3 crust is present on all aspects except north above 2500 m and ranges from 1-15 cm thick, with the thickest found in Yoho. Mid-pack persistent weak layers from Jan and Dec are down roughly 30 and 50 cm respectively. Facets and depth hoar make up the basal layers of the snowpack in most locations.
Weather Summary
The wind will diminish to the light range for the next two days, and calm-ish conditions are expected. A high-pressure system will build into the region on Wednesday. Lingering cloud will be present until Thursday. No precipitation is expected for a few days. Temperatures will be seasonal with -5 in the valley and -20 at the ridge line.
For more mountain weather, click HERE.
Terrain and Travel Advice
- Wind slabs may be poorly bonded to the underlying crust.
- Watch your sluff: it may run faster and further than you expect.
- Avalanche hazard may have improved, but be mindful that deep instabilities are still present.
Problems
Wind Slabs
Although winds have been light recently, small wind-slabs still exist in lee areas. These slabs sit on the Feb 3 crust, and could travel far and fast in steep terrain features.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Persistent Slabs
The persistent weak layers in the mid-pack are down roughly 30 and 50 cm with weak basal facets at the bottom of the snowpack. Sporadic avalanche activity has occurred on these layers and the theme seems to be steep thin snowpack areas in the alpine. Consider this in more committing terrain.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Feb 14th, 2024 4:00PM
