Avalanche Forecast

Issued: Mar 8th, 2013 9:09AM

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

Avalanche Canada jlammers, Avalanche Canada

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain on Sunday

Weather Forecast

A ridge of high pressure should persist for one more day bringing mainly clear skies for Saturday. Winds are expected to be light and northwesterly with the freezing level at 1900m.The ridge then flattens and a more zonal pattern is forecast to bring snowfall and seasonal temperatures to the region for Sunday and Monday. At this point there is significant model disagreement with the timing and intensity of this next system.

Avalanche Summary

Sun forecast for Saturday could trigger loose wet avalanche activity on steep solar features. Warming also has the potential to trigger cornice releases or deeper persistent slab avalanches in isolated terrain.

Snowpack Summary

Light amounts of recent snowfall sit on 60-100 cm of settling storm snow from last week.  Below 1400m in the north and 1700m in the south the light amounts of new snow overlie a thick rain crust. These recent accumulations may also exist as wind slabs in exposed terrain.At the base of last week's storm snow is a layer of buried surface hoar (February 20th). This layer was the culprit in most of the large avalanches that occurred last weekend. Snowpack tests continue to show sudden planar results and good potential for propagation. Triggering this layer is becoming more difficult, but I recommend avoiding any large slopes that did not release during the last cycle, especially when the sun pokes out this weekend. Below this the snowpack is generally well settled and strong.

Problems

Loose Wet

An icon showing Loose Wet
With forecast sun, loose wet avalanches will become likely on steep, sun-exposed slopes.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

An icon showing Persistent Slabs
60-120 cm of settled snow sits on a persistent layer of surface hoar. Extra caution should be given on all slopes over 30 degrees that did not previously slide, especially with solar warming on Saturday..
Conditions have improved, but be mindful that deep instabilities are still present.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 6

Cornices

An icon showing Cornices
Warming forecast or Saturday may trigger cornice falls. A large cornice fall may be what it takes to initiate a deep slab avalanche on the slope below.
Extra caution needed around cornices with current conditions.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 5

Valid until: Mar 9th, 2013 2:00PM