Archived

Avalanche Forecast

Feb 24th, 2015–Feb 25th, 2015

Alpine

1: Low

The avalanche danger rating in the alpine will be low

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Northwest Inland.

Generally safe avalanche conditions. Watch out for unstable snow on isolated terrain features.

Confidence

Good

Weather Forecast

Isolated light snowfall throughout the day on Wednesday with trace total amounts expected by the evening, and another 5 cm for Thursday. Freezing levels hovering around 800-1000 m and generally light winds. Expect clearing throughout the day on Friday as the high-pressure ridge rebuilds.

Avalanche Summary

Reports from Monday include numerous wet releases up to Size 2 out of steep sun-exposed slopes. Isolated cornice failures were reported, but no slabs were triggered on the slopes below. Several recent full-depth glide avalanches up to Size 3 were also observed nearby on all but North aspects.

Snowpack Summary

A variable snow surface generally includes a supportive crust with surface hoar or surface facets, all breaking down to corn snow with daytime warming and sun-exposure, but in general the snowpack is strong. Old wind slabs may be lurking in the alpine, or lower in glaciated drainages from recent katabatic winds. A layer of surface hoar buried in the upper snowpack has been reported in some areas, and is worth investigating before committing to any big alpine terrain. At the base of the snowpack, weak facets may be persisting.

Avalanche Problems

Wind Slabs

Thin, old, hard wind slabs may be lurking on lee and cross-loaded terrain at and above treeline, and fresher ones in glacial drainages from recent downslope winds. Cornices are also large, undermined, and weak, and could be strained by rapid cooling.

Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 1 - 3