Avalanche Forecast
Issued: Mar 16th, 2013 10:17AM
The alpine rating is Storm Slabs and Cornices.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Timing or intensity of solar radiation is uncertain
Weather Forecast
Synopsis: Northwest flow with limited moisture will bring cooler temps and flurries through the period.Sunday and Monday: Flurries, with some breaks in the cloud giving daytime warming both days. Afternoon freezing level around 500 m. Winds light westerly, becoming northwesterly on Monday.Tuesday: Light snowfall starting late in the day. Freezing level 200 m. Winds light southerly.
Avalanche Summary
On Saturday, natural slab avalanches were reported up to size 2.5 on north to east aspects in the alpine. Many were suspected of being triggered from cornice releases. Also on Saturday, loose snow avalanches were reported from steep terrain on solar aspects. On Friday, a skier triggered a size 2 avalanche on the March 9th surface hoar layer with a crown depth of 45 cm. Several other skier-triggered avalanches occurred on north and west aspects on the same weak layer.
Snowpack Summary
25-50 cm of recent storm snow rests on a variety of old snow surfaces, including crusts, previous wind slabs and surface hoar. Warmer temperatures and recent winds have now set this new snow into a reactive slab, with wind slabs building in exposed lee areas. The surface hoar (buried March 9th) is reported to be well-developed and fairly widespread, at treeline and alpine elevations. Recent snowpack tests have produced sudden failures with moderate loading force at this interface. The mid snowpack is generally well settled and strong. Cornices are large and untrustworthy, especially when the sun is out.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Mar 17th, 2013 2:00PM