Avalanche Forecast

Issued: Mar 4th, 2014 7:10AM

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

Alberta Parks burke.duncan, Alberta Parks

With upwards of 40cm of new snow in the forecast by Friday AM coupled with strong to extreme SW winds over the next 48 hours an increase in Avalanche Danger is certain.  Look for increased natural avalanche activity as a sign of increasing danger.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain on Wednesday

Weather Forecast

Milder temps are bringing with them strong to extreme winds with some variability across the forecast area.  The Aster Lake area has experienced strong winds all day while the Smith-Dorrien area had periods of calm with strong winds at ridgetop in the PM.  10cm of storm snow is forecast for Tuesday night with another 15cm on Wednesday and similar amounts forecast for Thursday.

Avalanche Summary

No new avalanches observed or reported.

Snowpack Summary

Snowpack depths overtop of the Feb 10 layer of SC/FC/SH vary from 35-80cm thick depending upon elevation and terrain exposure to winds. The bond at this interface is moving into the Hard range based on field tests over the past 2 days.

Problems

Persistent Slabs

An icon showing Persistent Slabs
The Feb 10 persistent weak layer is highly variable in nature (a mix of facets, sun crust, wind slab, surface hoar) and is still producing moderate to hard shears down 40 to 80cm in the snowpack.
Choose well supported terrain without convexities.>Avoid cross loaded slopes at or above treeline.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 5

Storm Slabs

An icon showing Storm Slabs
Easy to moderate shears at the storm snow interface. Observed 30-40cm of new snow at TL on wind loaded slope with cracking in the soft slabs being reported in numerous locations.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.>Caution in lee and cross-loaded terrain near ridge crests.>Caution in lee and cross-loaded terrain near ridge crests.>Be careful with wind loaded pockets, especially near ridge crests and roll-overs.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 5th, 2014 2:00PM