Avalanche Forecast

Issued: Nov 26th, 2019 4:00PM

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

Avalanche Canada shorton, Avalanche Canada

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Strong wind could create dangerous conditions in alpine terrain on Wednesday. 

Summary

Confidence

Moderate - Uncertainty is due to the extreme variability of wind effect on the snowpack.

Weather Forecast

TUESDAY NIGHT: Clearing skies, 40-60 km/h wind from the northeast, alpine temperatures drop to -16 C.

WEDNESDAY: Mostly sunny with some isolated flurries on eastern sides of the Coast Range, 40 km/h wind from the northeast, alpine temperatures around -18 C.

THURSDAY: Sunny, light wind from the northeast, alpine temperatures around -12 C.

FRIDAY: Sunny, light wind from the northeast, alpine temperatures around -6 C.

Avalanche Summary

No new avalanches have yet been reported in the region, but it's safe to assume the storm over the weekend caused natural avalanche activity at higher elevations.

For the early part of this week, the focus remains on the new snow, particularly in areas where winds may have blown it into deep and reactive wind slabs. Concern is reduced in areas where the new snow wasn't quite able to overcome the depth of ground roughness.

Snowpack Summary

Strong wind from the northeast will form new wind slabs on west and south facing slopes on Wednesday. 20 to 30 cm of snow accumulated in the region over the weekend. Observations in the region are limited, but we have indications that for most areas where previous snow cover existed, the new snow buried a thick crust. A MIN report from the Ashman area (west of Smithers) suggests the new snow bonded well to the crust, but that may not be the case elsewhere in the region. Given the lack of recent snowpack observations, we suggest carefully monitoring the bond of the new snow to this crust. Total snow depths are likely approaching 50-100 cm at alpine elevations in the Smithers area, with depths diminishing rapidly with elevation below 1500 m.

Problems

Wind Slabs

An icon showing Wind Slabs

As the wind shifts you may find old hard slabs on all aspects and softer fresh slabs on west and south facing slopes.This problem will likely be most pronounced at higher, more wind-exposed elevations.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Nov 27th, 2019 4:00PM