Avalanche Forecast
Issued: Jan 10th, 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,
Conditions are generally good. However, there is still a degree of uncertainty about persistent slabs at tree line. Dig down to confirm before committing to your line.
Summary
Weather Forecast
Valley temperatures will approach zero on Tues and Weds while the alpine will hover around -10. Snow is expected to start on Tues. Models are conflicted on the amount. Expect anywhere between 15cm and 40cm. Despite the amount of snow we receive, we can expect the winds to be strong to extreme from the SW.
Snowpack Summary
Recent storm snow totals are 20-50 cm at treeline. This sits on a spotty stellar/surface hoar layer in some locations. Wind effect in open areas in the alpine. Two weak layers from early Dec persist 50-100 cm down. These have been generally unreactive but still giving hard sudden planar results. The Nov. 5 basal crust/facets are currently dormant.
Avalanche Summary
Very little observed or reported avalanche activity today. Lake Louise patrollers managed to trigger a size 1.5 windslab in very steep unsupported terrain.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Tuesday
Problems
Wind Slabs
Previous winds have created slabs, however recent observations have only found them in specific alpine areas, and haven't been very reactive. Watch locally on your trip for slab formation. Some of these slabs will be buried under new snow.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Persistent Slabs
A spotty layer of stellars and surface hoar 25-50 cm down is most likely an issue in steep treeline terrain, but is present in some alpine locations. Two other layers from Dec persist and still produce hard sudden planar results.
- Convex features and steep unsupported slopes will be most prone to triggering.
- Dig down to find and test weak layers before committing to a piece of terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 11th, 2021 4:00PM
