Avalanche Forecast

Issued: Mar 29th, 2018 4:18PM

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

Avalanche Canada jmcbride, Avalanche Canada

New snow and wind Thursday night and Friday will add to recent storm slabs that sit on a touchy crust/facet/surface hoar layer. Choose conservative terrain and be especially wary of wind-loaded areas and solar aspects.

Summary

Confidence

Moderate -

Weather Forecast

TONIGHT: Flurries. Accumulation 10-15 cm. Ridge wind moderate to strong, west. Alpine temperature near -6. Freezing level valley bottom.FRIDAY: Flurries. Accumulation 5-10 cm. Ridge wind moderate to strong, northwest. Alpine temperature near -10. Freezing level valley bottom.SATURDAY: Mostly sunny. Ridge wind light, west. Alpine temperature near -8. Freezing level 800 m.SUNDAY: Cloudy, flurries. Accumulation 2-4 cm. Ridge wind light, southwest. Alpine temperature near -8. Freezing level 700 m.

Avalanche Summary

A widespread natural avalanche cycle up to size 3.5 was reported on Tuesday and Wednesday following the storm on Tuesday. Storm slabs from 50 to 100 cm deep were reported on all aspects between 1700-2500 m. Southerly aspects were the most reactive with numerous large and very large (size 2.5 - 3.5) avalanches running on a recently buried crust. While the natural cycle has tapered off, human triggered avalanches remain likely at treeline and above where the touchy late-March crust/surface hoar layer exists.

Snowpack Summary

Approximately 60 to 100 cm of recent storm snow has fallen with moderate to strong winds from the south / west. The storm snow sits on a variety of old snow surfaces buried late-March that consist of: sun crusts at lower elevations and on south aspects, and older storm snow or wind slabs up high. Surface hoar layers have been reported on shaded aspects at higher elevations. Persistent weak layers from early January and mid-December are still being reported by local operators but are generally considered dormant.

Problems

Storm Slabs

An icon showing Storm Slabs
All the new snow will take time to settle and stabilize. Storm slabs 60-100 cm thick have been especially touchy on southerly aspects where a crust has been buried by the recent storm snow as well as wind-loaded, high north aspects.
Use conservative route selection, stick to moderate angled terrain with low consequence.Avoid freshly wind loaded leeward and cross-loaded slopes

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Mar 30th, 2018 2:00PM