Avalanche Forecast

Issued: Nov 25th, 2015 8:25AM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Wind Slabs and Deep Persistent Slabs.

bcorrigan, Avalanche Canada

Cariboos.

Forecasters are working with limited information at this time. If you're out in the back country, send in your observations through the Mountain Information Network MIN

Summary

Weather Forecast

Arctic air has moved in from the north bringing clear skies and cooler than average temperatures. Strong northerly winds at ridge top are expected to continue through Thursday afternoon, and then back off to more moderate speeds by Friday after which winds should diminish to light values. Above freezing temperatures in the alpine are forecast to begin Friday morning and continue into the weekend but valley bottoms will remain well below freezing.

Avalanche Summary

We're working with very limited observations at the moment and we have not received any reports of recent avalanche activity.

Snowpack Summary

Monday's storm snow fell on a variety of old surfaces including crust, surface hoar and old settled snow. Arctic air moving into the region has resulted in northerly winds which may have formed small wind slabs on south facing features near ridge top. Warm temps and strong solar input formed a crust on south facing features which can be found underneath Monday's storm snow. There are at least three surface hoar layers in the snowpack buried on: Nov. 5th, Nov. 11th and Nov. 23rd. The first two have been largely unreactive. Facets may exist just above the ground on shaded slopes in the alpine.

Problems

Wind Slabs

Winds out of the north are likely driving wind slab formation on southerly features. These slabs are probably most problematic immediately lee of ridge crest, but you may encounter them in the right feature at treeline too.

Use ridges or ribs to avoid pockets of wind loaded snow.>Avoid freshly wind loaded features.>Be cautious as you transition out of wind sheltered terrain.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

November weak layers may become less reactive, but it's important to remember that there may be a weak layer of crust and facets near the ground. Most likely found his is probably on north through east facing alpine features.

Be aware of thin areas that may propogate to deeper instabilites.>Now is a good time to dig a snow profile (or two) and figure out how the snowpack changes with aspect and elevation.>

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

4 - 6

Valid until: Nov 26th, 2015 2:00PM