Avalanche Forecast
Issued: Mar 16th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Loose Wet and Cornices.
rgoddard,
Avalanche Canada
Warming temperatures and solar input will increase the avalanche hazard during the warmest part of the day.
Seek out northerly slopes with low overhead hazards for the best and safest riding in the afternoons.
Summary
Confidence
High
Avalanche Summary
On Wednesday there were two storm slab avalanches that were accidentally triggered by riders. These were on east and north aspects at treeline elevations. The layer that they ran on was a surface hoar/crust combo that the most recent storm snow buried. In both instances, the point where the avalanche was triggered was on a convex roll.
Snowpack Summary
The storm slabs, 30 to 50 cm thick, overlie a variety of surfaces, which include surface hoar, 3 to 5 mm, on shady slopes at all elevations, wind-affected surfaces at treeline and above, and sun crust on sunny aspects. Storm snow was accompanied by strong south winds. Expect wind slab formation at higher elevations. Solar aspects and lower elevations will be affected by day time warmer and nighttime freezing. Expect a crust in the morning and moist snow in the afternoon.
A layer of surface hoar or sun crust, aspect dependent, that was formed in mid-February can be found down 80 to 110 cm.
The lower snowpack includes a layer of weak sugary facets near the ground. These facets are slowly gaining strength and no recent avalanches have been reported on this layer. However, we continue to track the layer and watch for any signs of it becoming active.
Weather Summary
Thursday Night
Clear, no accumulation, winds southeast 10 to 15 km/h, treeline temperatures -5 to 0 °C .
Friday
Sunny, no accumulation, winds southerly 10 to 15 km/h, treeline temperatures -3 to 2 °C with freezing levels getting up to 1800 m.
Saturday
Mostly sunny with some cloudy periods, no accumulation, winds south 10 to 15 km/h, freezing levels possibly getting up to 1900 m.
Sunday
Sunny, no accumulation, winds south 10 to 15 km/h, freezing levels to 2000 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
- Make conservative terrain choices and avoid overhead hazard.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
- A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
Problems
Storm Slabs
Solar input may promote reactivity.
A storm from earlier in the week brought us 30 to 50cm of snow. This storm slab problem may remain reactive for longer than expected due to the uncertainty of how this new snow is binding with old surfaces.
It may seem calm now but the storm brought with it moderate to strong southwest winds. Expect to find deep deposits of wind transported snow.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Expect natural wet loose avalanches on steep sunny aspects when the sun comes out.
Aspects: South East, South, South West.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Cornices
Cornices have been building all season. Warm temperatures and solar input may cause them to fail.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Mar 17th, 2023 4:00PM
