Avalanche Forecast
Issued: Feb 22nd, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Storm Slabs and Loose Dry.
Ian Jackson,
New snow has refreshed the ski quality, but has been accompanied by lots of wind and sits on a weak facet layer in many locations.
Choose conservative terrain from which to assess conditions following this significant storm
Summary
Weather Forecast
A cold front will bring a good pulse of precipitation on Monday night (5-20 cm with highest amounts in the north and west) accompanied by strong westerly winds. Tuesday looks unsettled with light precipitation and easing winds. Wednesday looks to be cold, calm and clear before the next storm approaches Wednesday evening into Thursday.
Snowpack Summary
15-50 cm of storm snow over the last three days along with strong to extreme west winds has created windslabs in exposed alpine and treeline areas. This sits on top of either old wind effect in areas that were previously wind effected or soft facets in previously sheltered areas. The Jan. 27th interface of facets/sun crust is now down 30-70 cm.
Avalanche Summary
Limited visibility today, but an avalanche cycle occurred Sunday night within the storm. Bourgeau Left Hand ice climb ran size 2-3 (couldn't see the fracture line but debris ran below the climb). Ski hills were reporting limited results to size 1, mainly as soft wind slabs or storm slabs.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
Problems
Wind Slabs
Strong to extreme west winds have created wind slabs in the alpine and at tree line. An additional 5-20cm with wind is forecasted Monday evening. We suspect this will be touchiest in previously sheltered areas where the underlying facets were biggest
- Pay attention to overhead hazards like cornices which could trigger slabs.
- Use caution in lee areas. Recent wind loading has created wind slabs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Storm Slabs
15-50 cm of recent storm snow overlies a weak facetted layer in sheltered locations. As the snow settles into a slab, we suspect it will be reactive to human triggering. This problem will be most pronounced in areas with the most recent snow.
- The new snow will require several days to settle and stabilize.
- Use conservative route selection, choose moderate angled and supported terrain with low consequence.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Dry
New snow and strong to extreme winds continue to produce loose dry avalanche activity throughout the forecast region. Give the recent snow some time to settle before exposing yourself to steep overhead terrain.
- Avoid terrain traps, such as gullies, where the consequences of a small avalanche could be serious.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 23rd, 2021 4:00PM
