Avalanche Forecast

Issued: Jan 21st, 2014 9:11AM

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

ghelgeson, Avalanche Canada

Northwest Inland.

Summary

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 very limited precip for the northwest corner of the province. The ridge comes back with a vengeance Wednesday and should persist through the weekend.Wednesday: Freezing Level: 1500m; Precip: Trace Wind: Lht, W/SWThursday: Freezing Level: 3000m; Precip: Nil; Wind: Lht, W Mod NW at ridgetop.Friday: Freezing Level: 3000m; Precip: Nil; Wind: Lht, NW, Mod NW at ridgetop.

Avalanche Summary

No new avalanche observations from the weekend. 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. 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 prevalent 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.

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.

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

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

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.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

4 - 7

Valid until: Jan 22nd, 2014 2:00PM