Avalanche Forecast
Issued: Jan 19th, 2015 8:12AM
The alpine rating is Storm Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeReactive surface hoar layer with many rider triggered avalanches! The storm hit with strong winds and has slabbed up the snow. Combined with mild temperatures, the slab over the surface hoar layer will be more cohesive and propagation will increase.
Summary
Weather Forecast
Unsettled weather will persist into Tuesday with light snow and cloud. Temperatures are on a cooling trend and winds will be tapering down as a ridge of high pressure builds over the southern half of the Province into Wednesday.
Snowpack Summary
Close to 20cm of new snow overnight bringing recent storm snow to 45cm overtop the widespread Jan 15 surface hoar layer and crust on solar aspects. Expecting wind effected snow at higher elevations. The Dec 17 surface hoar layer is down 90-130cm overlying a crust below 2100m. The Nov 9 crust is a basal layer at the bottom of the snowpack.
Avalanche Summary
Backcountry users and field teams reporting several remote and rider triggered avalanches to size 1.5 down 20-50cm running on the Jan 15 surface hoar layer. Cheops North 4,natural avalanche dusted two riders on the uptrack. Natural avalanche cycle up to size 3.0 within the highway corridor began yesterday afternoon and into early this morning.
Confidence
Due to the number of field observations
Problems
Storm Slabs
~50cm of new snow overtop the widespread Jan 15 surface hoar layer. This layer was very reactive to human triggering yesterday. Expect this sensitivity to continue with the storm slab that formed overnight with the sustained strong southerly winds.
Be cautious as you transition into wind affected terrain.Avoid freshly wind loaded features.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
The new snow load or shallower avalanches could reawaken the Dec 17 surface hoar layer down 90-130cm. This layer is widespread at treeline, more spotty at alpine elevations and sits on a thick crust complex.
Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 20th, 2015 8:00AM