Avalanche Forecast
Issued: Jan 13th, 2021 8:00AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
Chris Gooliaff,
Mother Nature planted a warm, wet smooch on Rogers Pass last night.
30cm of new snow, mild temps, and strong/extreme SW winds have formed touchy storm slabs that are currently driving a natural avalanche cycle.
Summary
Weather Forecast
End of the storm this am, then a ridge will bring clearing skies and cooler temps.
Today: Cloudy with flurries, 5cm, FZL 1200m dropping during day, mod to extreme W winds at ridge-top
Tonight: Cloudy with clear periods, Alp low -14*C, mod/strong W winds
Thurs: Sunny periods, Alp high -3*C, mod SW winds
Fri: flurries, 5cm, Alp high -4*C, mod W winds
Snowpack Summary
A 35-40cm storm slab is covering a thin crust from sun and/or rime in exposed terrain, as well as surface hoar up to 10mm in the sheltered areas at treeline and below. The spotty Dec 26 surface hoar is down 70-90cm. The Dec 7th surface hoar/suncrust/facet layer is down 1.5+m. Crusts with facets persist at the base of the snowpack.
Avalanche Summary
A widespread natural avalanche cycle is underway in Rogers Pass, with large avalanches to sz 3.5 running into the valleys. Artillery control has also produced avalanches to sz 3.5 along the highway corridor.
Confidence
Problems
Storm Slabs
Snowfall, wind and warm temps have formed storm slabs overnight. These heavy slabs are failing on the underlying layers and there is an active avalanche cycle underway.
- Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Warm temps at tree-line and below accompanied the overnight dump. The new snow has a high moisture content and point releases from tree-bombs or failing snow mushrooms may gather significant mass.
- Watch for moist surface snow over crust on steeper solar aspects.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Jan 14th, 2021 8:00AM
