Avalanche Forecast

Issued: Feb 6th, 2015 9:04AM

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

ghelgeson, Avalanche Canada

Northwest Coastal.

There's DEEP powder and clearing skies in store for the weekend which sounds amazing, but we need to SLOW IT WAY DOWN and stick to conservative terrain as the snowpack adjusts to the recent huge load.

Summary

Confidence

Fair - Due to the number of field observations

Weather Forecast

Snowfall should slowly taper overnight. I'm expecting 10 to 40cm out of this last push. Winds should ease back (slightly), but I'm still expecting strong SW winds in the alpine Saturday. No snowfall is expected on Saturday, Sunday or Monday. Looks like it goes clear and dry through at least Tuesday.

Avalanche Summary

I suspect large natural avalanches are running Friday, but we do not have any observations at the moment.

Snowpack Summary

The NW Coast is THE place to be in the province right now. Arctic air has kept things cool and the snow totals are substantial. The storm has produced 50 to 100cm accompanied by screaming winds out of the E through SE. Observations are limited, but there has likely been a lot of slab development in wind exposed terrain at and above treeline. The late-January crust is thought to be down 50 to 150cm in the south of the region and about half this depth in the north. The mid-January rain crust and/or surface hoar layer is down over 150cm in the south and has generally become inactive though it may still be a concern in thinner snowpack areas. The November crust/facet combo near the bottom of the snowpack is thought to be generally well bonded but may still be reactive in the far north of the region.

Problems

Storm Slabs

Snowfall should taper before dawn Saturday morning, but suspect there is still potential for natural avalanche activity Saturday as the snowpack adjusts to the around a meter of storm snow. Choose well supported mellow terrain.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.>Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>Storm slab avalanches in motion have the potential to step down resulting in large avalanches.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 7

Persistent Slabs

There's a lot of uncertainty surrounding the deeply buried weak layers in the snowpack. This weekend I would make decisions based on the assumption that every slope above treeline has the potential to produce a very large and destructive avalanche.

Be aware of the potential for large, deep avalanches due to the presence of buried crusts and/or surface hoar.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

4 - 7

Valid until: Feb 7th, 2015 2:00PM