Avalanche Forecast

Issued: Feb 20th, 2014 9:06AM

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

bcorrigan, Avalanche Canada

Northwest Coastal.

The storm slab on a large weak layer is the most serious concern these days. Be conservative in terrain selection. Check out the latest. Blog post.

Summary

Confidence

Fair - Due to the number and quality of field observations

Weather Forecast

The bulk of the Pacific fronts should move out of the area by mid day Friday, although there may be some small "squall" precipitation events before the area cools down and clears off. Cold weather in the forecast for early next week.Thursday night: Freezing level at valley bottom, light flurries with possibility of 5 to 10cm in the forecast. Winds at ridge top gusting to50 Km/h.Friday: Freezing level around 100m , no precipitation in the forecast. Cool dry air moves into the region, ridge top winds up to 50Km/h.Saturday:Freezing level around 100m, no precipitation, sunny,..(Yay!), ridge top winds from the north @ 25 Km/h.Sunday: Cold clear weather, freezing level at valley bottom ridge winds around 30 Km/h.

Avalanche Summary

Reports of large natural avalanches have diminished int he past 24 hrs, but there have been a number of skier accidental, skier controlled and skier remote avalanches reported.

Snowpack Summary

Parts of the forecast region have received over 1.75m of cumulative storm snow which has now settled into a slab with a typical thickness of 60-90cm. This storm slab overlies a variety of facets, surface hoar, crusts, hard wind press, or any combination of these. Widespread whumpfing, cracking, natural avalanche activity and remote triggering at all elevations are a strong indication of poor bond between the new snow and these old surfaces. Snowpack tests show easy, sudden collapse within the storm slab. This storm slab problem will be with us for a long time as it is sitting on a large weak layer . Even when the ``whumping``stops,..it will still be dangerous, with potential for large, destructive avalanches as the slab settles and gets denser..

Problems

Storm Slabs

It's not necessary to be on a big slope to trigger it, that may be accomplished by reasonable proximity to the slope. Use careful route finding and cautious evaluation of the terrain where you plan to ride/ski. Scale back plans for big terrain.

Remote triggering is a concern, watch out for adjacent slopes.>Use conservative route selection, stick to moderate angled terrain with low consequences even if skiing in the trees>

Aspects: North, North East, East, South East, South, South West.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 5

Valid until: Feb 21st, 2014 2:00PM