Avalanche Forecast
Issued: Dec 18th, 2012 9:19AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
triley,
Avalanche Canada
Summary
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain on Thursday
Weather Forecast
Overnight and Wednesday: A weak ridge of High pressure will continue to cause cold and dry conditions during the day. The next Pacific frontal system is expected to move into the region by Wednesday evening. Light Westerly winds will become moderate Southwesterly as the storm moves in and brings 10-15 mm of precipitation, that should be snow (15-20 cms) at all elevations.Thursday: Strong Southwest winds and another 10-15 mm of precipitation for southern areas of the region. Freezing level should remain at valley bottoms.Friday: Flurries and gusty Northwest winds as a cold arctic airmass moves in from the Yukon.
Avalanche Summary
No observations were made due to poor visibility. One loud avalanche was heard running in the alpine during the afternoon.
Snowpack Summary
During the storm on Monday the height of the snowpack in Harvey Pass was 225 cms at 2000 metres. There was 20 cms of new snow and the storm slab was 45 cms thick. Moderate to strong Southwest winds were moving snow at treeline all afternoon. There was about another 15 -20 cms of snow after these observations. There was cracking in the soft slab ahead of skis when travelling. We suspect that stiffer wind slab was forming at higher elevations.
Problems
Storm Slabs
The new storm is expected to develop a storm slab on all aspects. The forecast strong SW winds may transport storm snow into thick and touchy slabs on North thru East aspects.
The new snow will require several days to settle and stabilize.>Be cautious of sluffing in steep terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 19th, 2012 2:00PM
