Avalanche Forecast

Issued: Nov 30th, 2019 4:00PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs.

Avalanche Canada ahanna, Avalanche Canada

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Firm snow conditions make for fast travel up high this weekend. Watch for pockets of hard wind slab in the alpine and tree line elevation bands.

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Saturday Night: Mix of sun and cloud, moderate wind switching to SW, alpine low -15 C.

Sunday: Increasing cloud, strong wind from the southwest, alpine high -7 C.

Monday: Mostly cloudy with isolated flurries, strong wind from the west, alpine high -5 C. Freezing level 600 m.

Tuesday: Mostly cloudy with isolated flurries, strong wind from the west, alpine high -4. Freezing level 700 m.

Avalanche Summary

There have been no recent reports of avalanches, but observations are limited this time of year so there is some uncertainty about the extent of current avalanche activity. Possible locations where avalanches could be triggered include near ridge tops and on slopes where the wind has deposited blowing snow. Early season avalanches can most easily propagate and run in areas where the underlying ground is smooth, such as on glaciers, rock slabs, scree, or grassy slopes.

If you see anything (or if you don't) while out in the field, please consider sharing that information with us and fellow recreationists via the Mountain Information Network (MIN).

Snowpack Summary

Recent reports from alpine and treeline elevations describe hard wind pressed snow on south to west aspects, and wind scoured crust elsewhere. Snow depths at these upper elevations sit around 100 cm, tapering quickly with elevation. Soft snow may still be found below treeline but the snow pack is quite thin here. Underneath the surface snow at the higher elevations lies a lower snow pack largely characterized by sandwiches of crusts and large, weak snow crystals (facets), as observed in another recent MIN report. We're also keeping an eye on a potential surface hoar layer (see video here). With few field observations, uncertainty remains on the distribution and reactivity of these layers.

Problems

Wind Slabs

An icon showing Wind Slabs

While wind slab avalanches are becoming less likely, watch for small pockets in extreme terrain where consequences of even a small avalanche could be high.

Aspects: South, South West, West.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 1.5

Valid until: Dec 1st, 2019 5:00PM