Avalanche Forecast
Issued: Mar 13th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
JSmith,
Avalanche Canada
Recently formed storm slabs will likely be reactive to human triggers on Monday; especially in wind affected terrain.
Riders may be surprised by widely propagating avalanches at treeline and below where storm slabs are sitting on a weak layer of surface hoar.
Summary
Confidence
Weather Forecast
SUNDAY NIGHT: Snow(above around 1000m); 5-10 cm / Moderate southwest winds / Low of -2 / Freezing level 1300 m.
MONDAY: Snow (above around 1300 m); 5-10 cm, and another 10-15 cm overnight / Moderate southwest wind / High of 1 / Freezing level 1600 m.
TUESDAY: Snow (above around1300 m); 5-10 cm, and another 5-10 cm overnight / Light southwest wind / High of 1 / Freezing level 1600 m.
WEDNESDAY: Mix of sun and cloud with isolated flurries; 0-3 cm / Light west wind / High of 0 / Freezing level 1500 m.
Avalanche Summary
Numerous natural and skier triggered storm slab avalanches up to size 2 were reported on Saturday. The storm slabs were most reactive were they were sitting on a sun crust or a weak layer of surface hoar.
Riders may get surprised by widely propagating storm slabs that are sitting on a weak layer of surface hoar.
Snowpack Summary
30-50 cm of recent snow and moderate southwest winds formed fresh storm slabs that have been most reactive in wind affected terrain; especially where slabs are sitting on a weak layer of surface hoar or a sun crust.
The 30-50 cm of recent snow is sitting on a variety of surfaces including hard wind affected snow, sun crusts on southerly slopes, and surface hoar on shady or sheltered slopes.
The late February persistent weak layer combination of crust, facets and surface hoar is down 40-50 cm. Reports suggest this layer is becoming less reactive in most areas.
Two additional persistent weak layers from late January and mid-February are down 80-120 cm. They both consist of surface hoar and/or melt-freeze crusts. Recent trends indicate these layers are gaining strength.
The most recent human triggered avalanches on these layers was in the southern Selkirks around the Valhalla, Kokanee, and Goat Ranges over the weekend of March 5-6th.
Terrain and Travel
- Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Be especially cautious as you transition into wind affected terrain.
- Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
Problems
Storm Slabs
30-50 cm of recent snow and moderate southwest winds formed fresh storm slabs that have been most reactive in wind affected terrain; especially where slabs are sitting on a weak layer of surface hoar or a sun crust.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 14th, 2022 4:00PM
