Brace for the next storm and avoid avalanche terrain at all elevations. Storm slabs from the alpine have the potential to run full path to the valley.
Storm slabs will build through the day and natural avalanche activity is likely. Avalanches from the alpine may reach below treeline elevations. Avoid avalanche terrain and overhead hazard.
The Interior regions will see the effects of the next atmospheric river by Tuesday. Heavy precipitation will fall as snow at upper elevations and rain lower. Strong to extreme southwest wind will exist and freezing levels will be on the rise from 1400 m to 2500 m Tuesday through Wednesday.
Monday Night: Periods of snow 10-20 cm. Alpine temperature -4 and freezing level 1500 m. Strong southwest wind.
Tuesday: Snow 20-30 cm at upper elevations. Alpine temperatures near -2 and freezing level 1700 m and rising to near 1900 m overnight.
Wednesday: Heavy snow at upper elevations 25-35 cm. Alpine temperatures near -4 and will slowly climb to 0 degrees in some areas. Freezing level rising to 2200 m. Strong southwest wind.
Thursday: Snow continues 10-20 cm. Alpine temperatures near -4 and freezing level dropping to 1400 m. Strong southwest ridgetop wind.
Storm slabs will build throughout the day. Natural avalanche activity is certain with this next weather system. Avalanches could run full path to lower elevations like the valley or simple, below treeline terrain.
On Monday, reports indicated several natural wet loose avalanches from 900-1200 m (below treeline) up to size 2.
A widespread natural avalanche cycle to size 3.5 was observed in the region on Sunday.
Up to a meter of recent storm snow fell at upper elevations over the weekend. At lower elevations, the precipitation fell as mixed rain/ snow or rain promoting a wet and saturated upper snowpack.
The average snowpack depth at treeline is 250 cm. The mid-November rain crust can be found down 70 to 130 cm and exists around 1900 m and below.
