Avalanche Forecast

Issued: Jan 19th, 2014 9:10AM

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

ghelgeson, Avalanche Canada

Northwest Coastal.

Summary

Confidence

Fair - Freezing levels are uncertain

Weather Forecast

A strong ridge of high pressure continues to dominate with no sign of a breakdown in sight. The NW Coast should fair slightly better than the rest of the province with a few pulses of precip. Freezing levels are on the rise throughout the forecast period.Monday: Freezing Level: 1200m. Precip: 3/8mm; Wind: Lht S, Strong SW at ridgetop.Tuesday: Freezing Level: Inversion, Above Freezing Air from 1300 2100m; Precip: Nil; Wind: Mod, SW.Wednesday: Freezing Level: Inversion breaking down late in the day, Above Freezing Air from 1300 2000m; Precip: 1/3mm Wind: Mod, SW

Avalanche Summary

No new avalanche activity reported on Saturday. The last significant cycle tapered off Jan 15th. It featured natural avalanches to size 4 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 north of the region between 900m and 1400m. It was a player during the last cycle even in low angled terrain. Look for it 70 -100 cm below the surface. Professionals continue to keep an eye on the basal facets which can be found down around two meters below the snow surface.

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 one meter 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: North, North East, East, South East, South, South West, West.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

4 - 7

Valid until: Jan 20th, 2014 2:00PM