Avalanche Forecast

A powerful storm is impacting the region

Thursday night: Overcast, 20-30 cm of new snow, strong south wind with extreme gusts at ridgetops, freezing level dropping to 1100 m.

Friday: Overcast, 20-30 cm of new snow, strong south wind with extreme gusts at ridgetop, freezing level climbing to 1400 m in the morning and dropping to 1000 m by late afternoon. 

Saturday: Mostly cloudy, 5-10 cm of snow, light southwest wind, freezing level near 1100 m. 

Sunday: Mostly cloudy, 10-15 cm of snow, moderate south wind, freezing level near 1000 m. 

Natural and human-triggered avalanches are likely on Friday.

There continue to be reports of both natural and explosive-triggered cornice falls (see this MIN report near Rainbow Mountain).

As much as 30-50 cm of snow could accumulate above 1400 m by the end day on Friday. Strong south winds will contribute to rapid slab formation, making natural avalanches likely. The combination of wind and snow has the potential to weaken cornices, which can act as triggers on slopes below. 

In isolated areas with a shallower snowpack in the region, a layer of facets, spotty surface hoar, and/or crusts buried in mid-February may still be preserved. There have been no avalanches reported on this layer; however, large triggers, such as an avalanche in motion, cornice fall, or intense loading from snow and wind have the potential to this deeper layer in areas where it may still exist.

The mid and lower snowpack is well settled and strong in most areas.

• Avoid all avalanche terrain during periods of heavy loading from new snow and wind.
• Watch for changing conditions today, storm slabs may become increasingly reactive.
• Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.