Avalanche Forecast
Issued: Nov 30th, 2016 3:50PM
The alpine rating is Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate - Forecast snowfall amounts are uncertain on Friday
Weather Forecast
Flurries and unsettled conditions continuing overnight and Thursday morning with freezing levels remaining around 1000 metres combined with light northwest winds. Winds increasing to strong from the southwest on Friday with 15-20 cm of new snow above 1500 metres. The freezing level should rise to 1500 metres at the beginning of the storm and then lower as a trailing cold front moves across the region from the northwest. Saturday should be overcast with another 3-5 cm of new snow combined with moderate to strong westerly winds.
Avalanche Summary
Thin soft slab avalanches size 1.0 continue to be reported in the Whistler area on Tuesday. Some reports from Monday of skier controlled soft slab avalanches up to size 1.5 where the surface snow has slabbed up above a less dense (one finger over fist) layer of recent storm snow.
Snowpack Summary
We have a few reports of a new surface hoar layer that may have been buried on Tuesday night (Nov 29th). Areas with this layer may develop a reactive storm slab on Friday when the new storm is forecast to arrive. Soft slabs about 20 cm deep have been reported from the Spearhead Glacier area on Tuesday. It sounds like these are most reactive where they are sitting on old wind blasted surfaces. Watch for shallow wind affected areas that may not gain strength as quickly as deeper well settled snowpack areas. Snow depths increased rapidly last week bringing treeline snow depths to about 200 cm. Much of this recent storm snow has settled and gained significant strength. That said, the last burst of wind and snow on Saturday and Sunday created reactive soft storm slabs which appeared to be especially touchy in higher, wind-exposed terrain.
Problems
Wind Slabs
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 1st, 2016 2:00PM