Avalanche Forecast

Moderate - Timing, track, or intensity of incoming weather system is uncertain

TONIGHT: Mostly cloudy, flurries. Accumulation 10-25 cm. Ridge wind strong to extreme, southwest. Alpine temperature near -5. Freezing level 1400 m.SATURDAY: Mostly cloudy, flurries. Accumulation up to 5 cm. Ridge wind strong easing to moderate, southwest. Alpine temperature near -5. Freezing level 1600 m.SUNDAY: Cloudy, flurries. Accumulation 10-15 cm. Ridge wind light, southeast. Alpine temperature near -5. Freezing level 1600 m.MONDAY: Cloudy, flurries. Accumulation 5-10 cm. Ridge wind light, east. Alpine temperature near -5. Freezing level 1500 m.

Thursday pockets of reactive wind slab up to size 1 in alpine lees were reported, as well as skier-triggered, loose, wet avalanches to size 1.5 on solar aspects up to 2100m, and below 1900m on north aspects. There were also reports from neighboring Glacier National Park on Thursday of a loose wet size 2 on a south aspect at 2100 m, and a size 4 wind slab that occurred overnight and is thought to have been cornice triggered on a north aspect at 2800 m.On Wednesday there were reports of wind slab activity on northerly aspects limited to the recent storm snow as well as loose wet activity on south-facing slopes.Tuesday there was a report of a natural size 2 wind slab avalanche that was observed on a north facing feature at 2800 m.On Monday natural loose wet avalanches to size 2 were reported on all aspects with the exception of north between 1500 and 2500 m. A skier triggered size 1.5 storm slab was reported from a west/northwest facing feature between 1800 and 2200, failing on a crust. And riders near Blue Lake also triggered a size 2 slab avalanche on buried surface hoar on a north aspect at 2000 m. Read MIN report here.

A thin surface crust is now present on all aspects to at least 2300 m. This crust likely goes even higher on south facing aspects, while 5-15 cm of cold snow can be found on high elevation north facing aspects. There are now a few different crusts in the upper 50 cm of the snowpack, with only the most recently crust posing a concern in wind-loaded areas. There is some lingering concern around the mid-March Persistent Weak Layer (PWL) in the alpine where it is found 60 to 110 cm below the surface. This buried crust/surface hoar interface was widely reactive last week, but has not produced any avalanche activity in the last few days. It is likely trending towards dormancy, but we need to keep it in the back of our minds as it is capable of producing large avalanches should it be triggered (think larger triggers such as; sleds, step-down from a surface avalanche or, a cornice collapse).Deeper persistent weak layers from December and January are dormant at this time.