Archived

Avalanche Forecast

Mar 10th, 2013–Mar 11th, 2013

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

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

2: Moderate

The avalanche danger rating below treeline will be moderate

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

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Kananaskis.

Clear skies are forecast for tomorrow. Solar radiation may be an issue. Pay attention to the aspect of your line or route and plan accordingly. MM

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain

Weather Forecast

The calm before the storm. Temperatures will drop to more seasonal ranges for the next 2 days. Winds will decrease to moderate and there will be almost no precip. BUT, starting on Tues a system is forecast to move in and bring some precip. The peak of the storm will be wed morning. Up to 32cm's can be expected. This system is almost another Pineapple Express. The freezing level will go up to 1500m.

Avalanche Summary

A natural sz2 in the east facing paths on Little Tent Ridge. A sluff from above looked to be the trigger. The starting elevation was the surprise with this avalanche. It happened at the TL elevation and originated in very skiable terrain.

Snowpack Summary

No significant new snow today, however there were some isolated flurries that left light amounts. Wind transport was the name of the game in the alpine today. Lots of redistribution of the recent storm snow today. Soft slabs can be expected from this wind. TL & BTL had another day of sun to soften and settle the snow. At TL, the upper layer was much more consolidated and cohesive with the layers below. BTL saw lots of sun crust and moist snow. Solar aspects will have challenging skiing.

Avalanche Problems

Wind Slabs

The winds today caused rapid loading with the redistribution of the storm snow. Soft slabs at TL & ALP were approaching the reactive level in specific areas. The bond with the existing slab interfaces needs to be carefully assessed.

Avoid lee and cross-loaded terrain near ridge crests.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 4

Persistent Slabs

This layer (Feb HSL) has been a suspected failure plain in a number of avalanches lately. A fresh sz2 on Little Tent Ridge was observed at TL elev and very skiable terrain.

Avoid convexities or areas with a thin or variable snowpack.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 4