Avalanche Forecast

Good

Monday: Mainly clear and sunny, with valley cloud. No precipitation. Light westerly winds. Freezing level valley floor. Tuesday/Wednesday: Flurries possible on western slopes. Light-moderate south-westerly winds. Becoming slightly milder.

Many large natural and human-triggered avalanches have been reported each day since Wednesday. Natural activity (up to size 3.5) spiked following the heaviest snowfalls on Tuesday night and Friday night. Skiers have been triggering avalanches (mostly size 1-2.5) accidentally and remotely. These are running on storm snow instabilities or persistent weaknesses in the upper snowpack. There have been some lucky escapes. Conditions will remain ripe for human-triggering after the more obvious signs of instability (like new snowfall, wind-loading and natural activity) die down.

Deep wind slabs exist on many aspects at all elevations. Storm snow totals range from about 60-140cm above the Feb 16. surface hoar layer and the Feb. 8 interface. The Feb. 8 interface is a combination of weak layers: in most locations it marks a widespread surface hoar layer. On steep south- and west -facing aspects, a sun crust that formed during the drought was also buried on Feb. 8th. This crust probably has a bit of faceting below it too, meaning that most terrain in the region has a weak layer in the upper snowpack. Recent remote and natural triggering indicates the touchy nature of these weaknesses. Large cornices threaten many slopes.