Archived

Avalanche Forecast

Jan 20th, 2014–Jan 21st, 2014

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

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

2: Moderate

The avalanche danger rating in the alpine will be moderate

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

2: Moderate

The avalanche danger rating in the alpine will be moderate

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

Regions: Northwest Inland.

Confidence

Poor - Due to the number of field observations

Weather Forecast

Synopsis: A frontal system takes a small bite out of the ridge Tuesday resulting in a few flurries for the Northwest Inland. The ridge comes back with a vengeance Wednesday and should persist through the weekend.Monday: Precip: 1/2mmTuesday: Freezing Level: Valley Bottom; Precip: 2/5mm 4/10cm late in the day; Wind: Mod, SW.Wednesday: Freezing Level: Valley Bottom; Precip: Nil; Wind: Mod, SW.Thursday: Freezing Level: 3000m Precip: Nil; Wind: Mod, W/NW

Avalanche Summary

No new avalanche activity reported on Saturday. The last significant cycle tapered off Jan 15th. It featured natural avalanches to size 3.5 with releases on all aspects and elevations.

Snowpack Summary

Previously strong winds have left widespread wind loading/wind damaged snow in their wake. Most of these wind slabs are probably growing old and tired but may still pose a problem in bigger terrain. Warming temps along with a bit of rain at lower elevations has formed a variety of crusts at and below treeline. The early January surface hoar is most active in the region at treeline. It was a player during the last cycle even in low angled terrain. Look for it in the upper 50 cm of the snowpack. Professionals continue to keep an eye on the basal facets which can be found down near the ground.

Avalanche Problems

Wind Slabs

Thin wind slabs that formed Saturday night and Sunday should be largely manageable. Be aware off the potential for deep hard wind slabs if you're sizing up bigger terrain in the alpine.

Be cautious as you transition into wind affected terrain.>Highmark or enter your line well below ridge crests to avoid wind loaded pillows.>

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 4

Deep Persistent Slabs

Two weaknesses have the potential to surprise folks: Surface Hoar around 50 cm below the surface and very weak basal facets near the ground. Vigilant slope by slope evaluation and/or a modest terrain approach are appropriate at this time.

Avoid convexities or areas with a thin, rocky or variable snowpack.>Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>Be aware of the potential for large, deep avalanches.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 4 - 7