Avalanche Forecast
Issued: Feb 21st, 2013 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
garth lemke,
Parks Canada
Some storm snow and winds are expected Friday into Saturday. Monitor loading patterns after the storm as surface instabilities will exist until the snow has stabilized.
Summary
Weather Forecast
A warm front followed by a cold front may pass through Friday into Saturday. Severe SW winds at 3000m and 50km/hr winds at 1500m may be here Friday am followed by 15cm of snow starting late Friday afternoon into Saturday am. Saturday and Sunday, winds will settle, temperatures will be seasonal, light flurries, and variable clouds.
Snowpack Summary
Variable windslabs exist in the alpine and treeline locations. They are bonding well to the previous surfaces. Many spots have been stripped of Saturday's storm snow revealing previous sustrugi and windslab surfaces with windpressed pockets in between. Weak facets dominate low elevations. Solid midpack bridges basal facets treeline and alpine.
Avalanche Summary
Thursday's patrol into Portal creek from Marmot basin revealed no new avalanches. No Patrol on Wednesday. Tuesday observed only a couple size 1.5 very steep loose avalanches @ 2600m appearing to be solar triggered. One size 2 thin slab was noted at 2700m E aspect on a very steep unsupported feature. They appear to be stopping where angle changes.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Friday
Problems
Wind Slabs
Saturday's 20cm of snow has evolved into a variable windslab and appears to be bonding well. It sits on a variety of surfaces such as previously hard slab and sastrugi.
Make observations and assess conditions continually as you travel.Assess start zones carefully and use safe travel techniques.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 22nd, 2013 4:00PM
