Avalanche Forecast
Issued: Apr 11th, 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.
GS,
Avalanche Canada
Our field team today reported good travel conditions to 3200 m in the alpine, but cold and windy. The next few days appear to be similar, with clearing forecasted for the weekend, making it a good time for alpine objectives. The ski quality is not awesome right now (wind effect), but the travel conditions are good on skis and feet.
Summary
Confidence
Avalanche Summary
An outlier of an avalanche was reported on Thursday: a size 3 slab on a SE aspect at 2800m above Bow Lake. We're unclear on the failure plane but assume this was a large windslab that released on a suncrust. Perhaps a cornice trigger.
We continue to monitor the Feb 3rd persistent weak layer as there have been three avalanches involving this layer in the last two weeks: a natural near Bow Summit, a skier remote in Purple Bowl and a skier accidental at the Cathedral Glades.
Snowpack Summary
Surface crusts exist on solar aspects, and up to ~2000 m on north aspects. Above this the snow surface is dry, wind-affected snow. The upper snowpack contains several buried crusts.
The midpack is generally well settled down to the February 3 persistent weak layer which remains a concern in shallow snowpack areas on northerly alpine aspects. In these areas, no crusts are found in the upper snowpack and the midpack remains thin and weak.
Weather Summary
A short-lived weather system will cross the region this evening, depositing up to 2-5 cm over higher elevation terrain before it clears early Friday morning. In its wake, expect scattered flurries on Friday and a mix of sun and clouds on Saturday. Freezing levels will reach the 2100-2400 range on both days with moderate westerly winds at the ridge crests.
The longer-term models show a good dump of snow on Monday.
Terrain and Travel Advice
- Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Wind Slabs
15-20 cm of snow over the past 7 days combined with strong southwest winds earlier this week has created widespread wind effect above treeline. New windslab development has been limited in the past 24 hours, but watch for lingering pockets of slab in leeward and unsupported areas.
Aspects: North, North East, East.
Elevations: Alpine.
Likelihood
Expected Size
Persistent Slabs
The Feb 3 layer is down 60-130 cm. In shallow snowpack areas on northerly alpine aspects, this layer may still be sensitive to skiers, with remote triggering observed in a couple of instances last week. All recent avalanches that initiated on this Feb 3 layer stepped down to the basal facets/ground.
Aspects: North, North East, East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 12th, 2024 4:00PM
