Avalanche Forecast

Issued: Mar 25th, 2018 5:19PM

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

Avalanche Canada mgrist, Avalanche Canada

Strong winds and incoming snow are a recipe for touchy avalanche conditions up high. Sheltered terrain lower down (with no overhead hazard) is a good option this week.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain on Monday

Weather Forecast

Snowin' and blowin' for the next two days... sounds like a good time to stick to sheltered trees down low.  SUNDAY OVERNIGHT: Snow begins (5-10cm).MONDAY: Snow (10-15 cm). Moderate to strong southwest winds 35-60 Km/hr. Freezing level to 1300 metres with alpine high temperatures of -7.TUESDAY: Snow (10cm). Moderate to strong west winds, Freezing level 1500 metres with alpine high temperatures around -1.WEDNESDAY: A mix of sun and cloud and isolated flurries.  Moderate southwest winds 20-40 Km/hr. Freezing level to 1200 metres with alpine high temperatures around -5.

Avalanche Summary

On Saturday, size 1-1.5 wind slabs were reported near Valemount, running naturally and also when cut by skiers on high north/east facing aspects near 2300m. Slabs ran within the storm snow, crown heights approximately 20cm.Reports from a week ago included several small (size 1) skier-triggered and ski cut storm slabs on high elevation north aspects. These slabs failed on a surface hoar layer buried earlier this month that is mentioned in our snowpack discussion, found down about 25 cm at the time. Looking forward, fresh storm slabs, blown in by moderate to strong winds are the chief concern.

Snowpack Summary

Convective snowfall coupled with strong southerly winds brought a wind-affected 15-30 cm of new snow to the region since Thursday night. The new snow has buried a couple of recent layers of storm snow or wind slabs up high, or sun crusts at lower elevations and on south aspects. Surface hoar layers have been reported on shaded aspects at higher elevations and can likely now be found at approximately 20 and 40 cm below the surface. New snow amounts taper with elevation and below about 1800 m, reduced accumulations have buried a supportive crust on all aspects.Persistent weak layers from early January and mid-December are still being reported by local operators. They are generally considered dormant, but could wake up with a surface avalanche stepping down, a large cornice fall, or a human trigger in a shallow or variable-depth snowpack area. These layers consist of sun crust, surface hoar and/or facets.

Problems

Storm Slabs

An icon showing Storm Slabs
Strong winds and new snow will make for touchy conditions at higher elevations.
Be cautious around high, sheltered north aspects where buried surface hoar may be preserved.Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 3

Valid until: Mar 26th, 2018 2:00PM