Avalanche Forecast
Issued: Nov 29th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
zryan,
Avalanche Canada
Be cautious as you transition into wind-affected terrain. Easterly outflow winds have started to form fresh wind slabs in unusual areas and at lower elevations than is typical.
Cold temperatures, short days, and early season hazards should factor into your trip planning. Be prepared for an emergency and leave yourself plenty of daylight to get home safely.
Summary
Confidence
Moderate
Avalanche Summary
Over the weekend, A MIN report from the Babines shows a skier-triggered wind slab avalanche that occurred on a south aspect at treeline.
Another MIN from Sunday has photos of wind slab avalanches that likely occurred during the storm on Saturday.
Looking forward to Wednesday, we expect northeast outflow winds to form fresh wind slabs on south and west-facing slopes. These wind slabs will be in atypical areas that are usually windward, which may take riders by surprise.
Thank you for all the great Mountain Information Network reports! They are beneficial to us in the early season when we have limited information and data sources. Please keep them coming!
Snowpack Summary
Last week's storm delivered 50-100 cm of snow and strong southwest ridgetop winds. Thick, wind-loaded areas and large cornice growth were observed at treeline and above.
Over the past 2 days, strong easterly outflow winds and cold temperatures have started to stiffen the upper snowpack and strip windward, easterly aspects. In areas where the storm snow remains loose and powdery, these winds may redistribute it into fresh wind slabs.
This recent new snow overlies a variety of potentially problematic snow surfaces including sugary, faceted snow, and a crust at low elevations and solar aspects.
The depth of the snowpack at treeline varies from 80-140 cm and tapers rapidly below treeline.
Many early-season hazards such as rocks, stumps, and open creeks exist below treeline.
Weather Summary
Tuesday night
A mix of sun and cloud, light snowfall with up to 1 cm accumulation. Easterly outflow winds increasing to 50-80 km/h. Temperatures dropping to -27 C at treeline.
Wednesday
Mainly sunny. Easterly winds 40-80km/h. High temperature at treeline -25 C.
ThursdayPartially cloudy. Light variable winds. Temperatures rising, high temperature at treeline -13 C.
FridayA mix of sun and cloud. Easterly winds 40-60km/h. High temperature -16 C at treeline.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
- Use ridges or ribs to avoid areas of wind loaded snow.
Problems
Wind Slabs
Recent winds have shifted to the northeast and may form fresh wind slabs on south and west-facing slopes that are typically more windward.
Watch for lingering wind slabs formed by the strong southwest winds that accompanied the storm ending last weekend. These slabs are likely becoming stubborn to trigger in many areas.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Nov 30th, 2022 4:00PM
