Avalanche Forecast

Issued: Mar 2nd, 2015 7:31AM

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

jlammers, Avalanche Canada

South Rockies.

A surging Arctic front should deliver light snow and moderate winds, which will elevate the avalanche danger slightly.

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Monday

Weather Forecast

Mainly clear skies are expected for the forecast period as a dry ridge rebuilds. Ridge top winds are expected to remain generally moderate from the northwest. Freezing levels are forecast to sit at valley bottom for Tuesday and Wednesday, and then rise to about 1600m on Thursday.

Avalanche Summary

No new avalanches have been reported recently but observations are limited.

Snowpack Summary

A few centimeters of new snow sits on the previous snow surface, which was a mix of surface hoar, crusts, wind affected surfaces, or dry powder. The most prominent snowpack features is a thick supportive crust around 10-30 cm below the surface. It extends up to around 2200m. Below this elevation the crust is effectively capping the snowpack, preventing riders from tickling deeper persistent weak layers. In alpine areas, where the crust is not present or is less thick, it could still be possible to trigger a deep avalanche from sparsely covered rocky slopes or with a heavy load (i.e. cornice fall).

Problems

Wind Slabs

Forecast new snow and moderate northerly winds could combine to create fresh wind slabs in exposed lee terrain. The new snow could also sluff off as loose dry avalanches in steep sheltered terrain.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>Use ridges or ribs to avoid pockets of wind loaded snow.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

Triggering this problem is unlikely, but be wary of high north aspects where the near-surface crust is absent or breakable, and use caution around large overhanging cornices.

Be aware of thin areas and rock outcroppings where it may be possible to initiate an avalanche that fails on one of the deeply buried weak layers.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

3 - 6

Valid until: Mar 3rd, 2015 2:00PM