Avalanche Forecast
Issued: Jan 19th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Aaron Beardmore,
Forecasted extreme wind overnight on Tuesday has created uncertainty about wind slabs in the alpine and treeline. Investigate locally and approach cautiously until you get a feel for conditions. Great conditions expected on Thursday and Friday.
Summary
Weather Forecast
A wind event is expected to persist throughout the region tonight and into the early hours of Wednesday (Extreme from the West). A slight cooling trend will follow the wind event. Expect calm conditions and benign weather on Thurs/Fri.
Snowpack Summary
Up to 10 cm of snow over thin sun crust on steep solar aspects and over previously wind scoured terrain at treeline and above. Jan 11th interface down 20-35 cm producing mod to hard results. Dec 25th, 13th and 7th layers down 50-120 cm and generally produce hard or no results. A rain crust exists on surface below 1500 m in eastern areas.
Avalanche Summary
A large natural cornice fall was observed on Rockwall Peak. No slab was associated with the cornice fall on the fan below. Otherwise, no avalanches were observed or reported.
Confidence
Wind effect is extremely variable on Wednesday
Problems
Wind Slabs
Winds Tuesday overnight will add to the wind slabs present in steep lee areas, but there may be little snow left to transport. Treat lee loaded areas with extra caution especially if entering large steep terrain features.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Use caution in lee areas in the alpine and treeline. Recent storm snow has formed wind slabs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Several persistent weak layers are present in the top meter of the snowpack. Generally, they are not reactive to skier traffic but we still get occasional reports of avalanches on one of the layers, usually on steep convex rolls or in thin areas.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Jan 20th, 2021 4:00PM
