Avalanche Forecast

Issued: Feb 4th, 2015 7:54AM

The alpine rating is high, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Storm Slabs.

Avalanche Canada ghelgeson, Avalanche Canada

The exact timing of the storm is a little hard to pin down for Thursday. Danger ratings are based on the assumption that it's snowing/raining/windy for most of the day.

Summary

Confidence

Fair - Timing of incoming weather systems is uncertain on Thursday

Weather Forecast

The first of three distinct waves of well organized warm precipitation accompanied by strong SW winds should impact the South Coast Inland around lunch time Thursday. The rain/snow line should initially be around 1000m, steadily rising to 2300m by Thursday night as precipitation intensity increases. The second wave should arrive mid-day Friday with the freezing level hovering around 2300m. The final wave is expected to make its way inland Saturday evening. Storm totals in mm of water are expected to be in the 10 - 100 range.

Avalanche Summary

No new avalanche activity reported Tuesday. On Monday, skiers were triggering soft wind slabs in immediately leeward features up to size 2. On Sunday, small soft wind slabs were reported to be reactive to skier triggering. Sluffing from steep terrain features was also reported.

Snowpack Summary

10 - 30cm of new snow overlies a hard rain crust that exists up to at least 2100m. In exposed terrain, the new accumulations have been shifted by strong SW winds into wind slabs up to 40cm thick which may be especially reactive due to the underlying crust. Deeper snowpack weaknesses have become unreactive on account of the strong capping crust layer.

Problems

Storm Slabs

An icon showing Storm Slabs
Avalanche activity is expected to be widespread at and above treeline Thursday afternoon. Screaming winds with a dynamic cool to very warm and wet storm suggests that avoidance is likely the best mitigation strategy once the storm arrives.
Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>Avoid exposure to overhead avalanche terrain, avalanches running on the thick crust may run further than you think.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 4

Valid until: Feb 5th, 2015 2:00PM