Avalanche Forecast

Issued: Nov 17th, 2015 5:59PM

The alpine rating is high, the treeline rating is considerable, and the below treeline rating is low. Known problems include Wind Slabs, Loose Dry and Storm Slabs.

Avalanche Canada Lisa Paulson, Avalanche Canada

Avalanche control planned for Sunshine tonight, Bosworth, and Mt. Stephen on Wednesday. Depending on results we may also do Simpson, Whymper, and clean up on Sunshine. Please no recreational activities in these areas on Wednesday.

Summary

Weather Forecast

The cold front passes by midnight: the snow should end, temperatures continue to drop, and winds should taper.  For Wednesday, expect isolated flurries and lighter winds from the W  gusting to 50 km/hr. Stable weather is forecasted for the remainder of the week with 2 nights of -18C temperatures (Thur & Fri) and warmer for the weekend (-12C),

Snowpack Summary

At treeline in the Emerald Lake slide path there was 115 cm of snow and 60 cm at 1500 m. 30 cm low density snow fell so far today and overlies a suncrust found 2000 m and below. Field tests show moderate failures with potential for propagation at the new storm interface and a harder sudden collapse near the base of the snow pack.

Avalanche Summary

Poor visibility today. Only small avalanches ski cut in the Sunshine area, nothing stepping down to deeper layers. In the alpine, expect some activity where the winds have been moderate SW all day and loose snow avalanche can be expected in steep gullied terrain.

Confidence

Problems

Wind Slabs

An icon showing Wind Slabs

Strong winds have been redistributing the loose snow into leeward areas where windslab failures should be expected up to 1 m thick in leeward terrain. Continued moderate SW wind tomorrow will add to the load causing natural avalanches.

  • The new snow will require several days to settle and stabilize.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Loose Dry

An icon showing Loose Dry

Expect sluffing in steep gullied terrain with continued moderate SW wind Wednesday. Good time to pick climbs not exposed to avalanche hazard.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Storm Slabs

An icon showing Storm Slabs

The entire snowpack is a result of 2 recent storms and may sit on early season facets in some locations. Following the first storm there were a few alarmingly wide propagations to size 3 on this layer in the rockies. We have few alpine observations.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Nov 18th, 2015 4:00PM