Avalanche Forecast

Issued: Apr 9th, 2013 11:30AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Cornices and Loose Wet.

Avalanche Canada ghelgeson, Avalanche Canada

Summary

Confidence

Poor - Due to limited field observations

Weather Forecast

Synopsis:  Precip should taper off by Wednesday morning.  The trailing cold front brings freezing levels down to Valley Bottom with no significant precipitation expected.  Colder temps and broken cloud cover should persist through Thursday evening before a weakening low makes landfall Thursday night, persisting through Friday.Wednesday: Freezing Level: Near valley bottom. Precip: Isolated convective flurries. Wind: Mod, SW.Thursday: Freezing Level: Valley bottom. 1800m Precip: Nil Wind: Mod, SWFriday: Freezing Level: 500m Precip: 5/10mm – 8 – 15cm Wind: Strong, SE.

Avalanche Summary

No new avalanche activity reported Monday.  Natural and skier triggered loose wet sluffs were reported in steep sun-exposed terrain on Sunday. On Saturday, widespread loose dry sluffing was reported in steep terrain running on a recently buried crust.

Snowpack Summary

15-25 cm of new snow sits on a melt-freeze crust at most elevations. Warm temperature and solar radiation resulted in moist snow on solar aspects and lower elevations. A new surface crust may form before the next system arrives on Tuesday night. Pockets of wind slab have developed in exposed lee terrain and cross-loaded gullies. 30 - 60 cm of snow overlies a crust, old wind slabs or surface hoar layer buried on March 9th. The distribution of the surface hoar is also highly variable and it does not exist in every drainage. I would still remain cautious and continue to dig and test before diving into my line. Deeper in the snowpack, basal facets may resurface as a concern with continued mild temperatures.Cornices have become well-developed and could easily become unstable during periods of warm weather or direct solar radiation.

Problems

Wind Slabs

An icon showing Wind Slabs
Thin new wind slabs are likely in exposed lee terrain and cross-loaded features. Triggering may be possible in steep terrain.
Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Cornices

An icon showing Cornices
Large cornices may be weak and fall off naturally during warm temperatures or from increased loading.
Give cornices a wide berth when travelling on or below ridges.>Pay attention to overhead hazards like cornices.>

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 6

Loose Wet

An icon showing Loose Wet
Loose wet avalanches are possible at lower elevations where precipitation may fall as rain or wet snow.
Watch for wet loose or slab activity with forecast rain and/or wet snow.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Apr 10th, 2013 2:00PM