Avalanche Forecast
Issued: Mar 20th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Persistent Slabs and Loose Wet.
ahanna,
Avalanche Canada
Time to switch your avalanche mindset back to winter. A cold front from the NE brings heavy upslope snowfall which will fall over a slippery crust.
Summary
Confidence
Moderate
Avalanche Summary
Numerous naturally triggered loose wet avalanches were reported on sunny aspects at all elevations on Monday. A naturally triggered size 2 wet slab on an east aspect below treeline and a size 2 cornice failure were also reported.
By Tuesday, natural activity had slowed down with only a few size 1 loose wet reported.
Snowpack Summary
10 to 25 cm of cold new snow falls over predominantly crusty surfaces. Below 1500 m, the new snow (or rain) may fall on an already moist upper snowpack.
A widespread, hard crust with facets above is buried around 80 cm deep in the South Rockies and around 200 cm in the Lizard range. It continues to be the primary layer of concern for human triggering of very large persistent slab avalanches.
Weather Summary
A cold front from the northeast stalls over the Divide, bringing heavy upslope snowfall to the region on Thursday.
Wednesday night
Cloud with isolated flurries bringing a trace of snow. 10 to 25 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1000 m.
Thursday
10 to 25 cm of snow, with rain below 1300 m west of Elkford and in the Lizard and Flathead areas. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1500 m.
Friday
5 to 10 cm of snow overnight then cloudy. 10 to 20 km/h northeast ridgetop wind. Treeline temperature -8 °C. Freezing level 1000 m.
Saturday
Cloudy with isolated flurries, up to 5 cm. 20 to 30 km/h northeast ridgetop wind. Treeline temperature -10 °C. Freezing level 800 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
- Carefully monitor the bond between the new snow and old surface.
- Avoid exposure to overhead avalanche terrain during periods of heavy loading from new snow, wind or rain.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
Problems
Storm Slabs
New snow will likely bond poorly to crusty surfaces. Slabs will be most likely triggered in wind-loaded lees. Loose dry avalanches can be expected in steep terrain where snow hasn't formed a slab.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
A crust with weak facets above is down 80 to 200 cm. Steep or convex terrain features with a shallow or thin to thick snowpack at treeline and above are the most likely places to trigger this layer.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Loose wet avalanches will become increasingly likely at elevations where precipitation falls as rain. If triggered loose wet avalanches may step down to deeper layers, resulting in very large avalanches.
Aspects: All aspects.
Elevations: Below Treeline.
Likelihood
Expected Size
Valid until: Mar 21st, 2024 4:00PM
