Avalog
Register
Get forecast notifications
Create an account to receive email notifications when forecasts are published.
Register
Login
Archived

Avalanche Forecast

Dec 5th, 2015–Dec 6th, 2015
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
3: Considerable
The avalanche danger rating below treeline will be considerable
Alpine
4: High
The avalanche danger rating in the alpine will be high
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
3: Considerable
The avalanche danger rating below treeline will be considerable
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
3: Considerable
The avalanche danger rating below treeline will be considerable

Regions: Glacier.

Avalanche hazard is increasing as the storm slab gains cohesion. Avalanches can run far on low elevation surface hoar.

Weather Forecast

A SW flow brings a series of storms over the next several days. Expect light precipitation today with freezing levels around 1500m and moderate to strong SW winds. Precipitation intensifies late this afternoon with up to 12cm of heavy snow overnight. Freezing levels climb to 1700m on Sunday with ongoing light precipitation.

Snowpack Summary

Up to 25cm of heavy storm snow affected by warm temps and wind has formed a soft slab over a widespread layer of large surface hoar. On solar aspects, the surface hoar sits on a sun crust. The Nov 5 surface hoar layer is buried down 80-100cm. On true north aspects, a basal weakness may become unstable with the recent additional snow loading.

Avalanche Summary

Numerous avalanches were observed from the highway corridor east of Rogers Pass, up to size 2.5. Avalanches starting high in the alpine triggered additional slabs at lower elevations. Whumpfing and cracking was observed below treeline.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Avalanche Problems

Storm Slabs

25cm of heavy new storm snow has combined with strong SW winds to form a slab over a touchy, widespread surface hoar layer. This slab is easily triggered by riders and has the potential to propagate into larger than expected avalanches.
Space out and travel quickly through runout zones of avalanche paths.Avoid open slopes and convex rolls where buried surface hoar may be preserved.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 2 - 4

Wind Slabs

Strong southerly winds are transporting storm snow and forming wind slabs in exposed areas. When triggered, cohesive wind slabs have the potential for wide propagation where they overlay the Dec 2nd surface hoar.
Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 3