Avalanche Forecast
Issued: Feb 13th, 2015 8:16AM
The alpine rating is Persistent Slabs and Storm Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Intensity of incoming weather systems is uncertain
Weather Forecast
Temperatures start cooling on Saturday with the passage of a cold front. 10-15 mm precipitation is expected with the front overnight Friday/ Saturday, tapering to flurries on Sunday. The freezing level falls to around 1500 m on Saturday. Monday is dry and cool, with a chance of sun. Winds are moderate NW, easing to light by late Sunday.
Avalanche Summary
Size 1.5 wind slabs and a size 2.5 storm slab were triggered naturally on Thursday. A number of cornice collapses have been reported over the last few days. Loose wet avalanches failed naturally in steep terrain on Wednesday in response to warming. Also on Wednesday, explosives triggered a couple of size 2 slabs, which failed on the late-Jan crust. Human-triggering of the persistent slab remains possible.
Snowpack Summary
New snow may have been shifted into wind slabs on lee features at alpine and treeline elevations. Keep your eyes open for cornices, which may be large and unstable. A week or so of very warm temperatures has affected the snowpack, creating moist surface layers up to around 2000m. At low elevations, the snowpack may now be relatively uniform. The late-Jan crust/surface hoar layer, buried around a metre deep, remains a key concern, as it could still be human-triggered and could produce a destructive avalanche. The mid-January surface hoar is typically down 80-120cm and is unlikely to be triggered, apart from in a thin or rocky snowpack area. The mid-December weak layer is down over 120cm, but has been generally unreactive lately. Basal weaknesses remain in the back of operators' minds.
Problems
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 14th, 2015 2:00PM