Avalanche Forecast

Issued: Mar 30th, 2017 3:45PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Wind Slabs and Deep Persistent Slabs.

triley, Avalanche Canada

Northwest Inland.

Forecast new snow and wind are expected to develop new wind slabs in the lee of southwest winds.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Friday

Weather Forecast

Overnight: Cloud and strong southwest winds developing overnight, with 3-5 cm above 700 metres by morning. Friday: Overcast with strong southwest winds, another 3-5 cm during the day with daytime freezing up to 1200 metres. Saturday: Overcast with a few cm of new snow and moderate southwest winds. Sunday: Overnight freezing down to valley bottoms. Overcast with flurries or light snow and moderate westerly winds.

Avalanche Summary

Storm slabs up to size 2.5 were reported from the western extent of the region in the Howson's, where the snowpack is more like the Northwest Coastal region. No new avalanches reported from the rest of the region.

Snowpack Summary

Light snow combined with moderate southwest winds has developed wind slabs in the alpine and in some exposed treeline locations. Periods of sun and high daytime freezing levels have developed crusts below treeline and on sun exposed terrain at all elevations. The snow may be moist or wet below treeline during the warmest part of the day. The Mid-February crust and facet layer was reported to be down 75-90 cm in the Houston Telkwas sled area on Wednesday. The deep persistent weak layer of facets and/or a crust that were buried early in the winter are still lingering near the bottom of the snowpack. This MIN report found the deep weak layer strengthening in the Telkwas.

Problems

Wind Slabs

Expect new wind slabs to develop due to the forecast new snow and wind.

Be careful with wind loaded pockets. Be aware of wide variation in snowpack depthUse caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Deep Persistent Slabs

A weak layer of facets and/or a crust that developed early in the winter lies near the bottom of the snowpack. Any change in the weather may affect the likelihood of triggering this deep weak layer.

Choose well supported terrain without convexities.Avoid steep convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely

Expected Size

1 - 3

Valid until: Mar 31st, 2017 2:00PM