Archived

Avalanche Forecast

Jan 23rd, 2014–Jan 24th, 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 Coastal.

Confidence

Good

Weather Forecast

Friday and Saturday: Sunny with cloudy periods and valley fog likely. Light winds. Freezing level reaching 3500 m with alpine temperatures close to +10 C, but cooler in valley bottoms. Sunday: Mostly sunny with valley fog likely. Light winds. Freezing level reaching 3000 m with alpine temperatures close to +5 C, but cooler in valley bottoms.

Avalanche Summary

Reports from Wednesday include warm temperatures causing a few natural small loose wet avalanches as well as a Size 3 glide avalanche.

Snowpack Summary

The surface snow is likely undergoing a melt-freeze cycle on all but high elevation shady aspects, while the entire snowpack may even be trending isothermal at lower elevations. On shady aspects, over 20cm of recent storm snow (more on wind-loaded slopes) is settling and bonding well to the previous snow surface, which includes a crust up to treeline elevations. Well preserved surface hoar may be found buried in the upper snowpack on sheltered treeline slopes and below, and has been most active in the northern parts of the region between 900m and 1400m elevation. A well settled mid and lower snowpack may rest on basal facets, especially in thin snowpack areas at higher elevations.

Avalanche Problems

Loose Wet

Generally small, slow, and often limited to extreme cliffy terrain; however, these dense avalanches can easily knock you off your feet and take you for a ride.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>Watch for clues, like sluffing off of cliffs, that the snowpack is warming up. >

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 3

Deep Persistent Slabs

Basal facets, buried surface hoar, and glide avalanches are all expected to become more sensitive to triggering with warm temperatures and solar radiation. Although tricky to pinpoint when and where they might occur, the consequences could be severe.

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.>Avoid slopes with glide cracks.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 4 - 7

Wind Slabs

Although becoming stubborn, isolated wind slabs below ridge crests may still be sensitive to human triggers.

Start on small terrain and slope-cut the top of slopes before riding them.>Highmark or enter your line well below ridge crests to avoid wind loaded pillows.>The recently formed wind slabs will need a couple days to settle out.>

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1 - 3