Avalanche Forecast

Issued: Apr 18th, 2014 9:32AM

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

rbuhler, Avalanche Canada

Northwest Inland.

This bulletin was created using very limited field data. If you are out in the mountains, please send your observations to forecaster@avalanche.ca

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

Unsettled conditions and light precipitation are expected for most of Saturday before the next low pressure system hits the north coast Saturday evening. There is quite a bit of uncertainty as to how much precipitation will make it into the inland region and there is a possibility that the storm will be confined to the coast. Light scattered precipitation is expected for Sunday and Monday.Saturday: Precipitation 1-3mm, freezing level am: 1000m pm: 1500m, ridgetop wind: moderate SE-SWSat. Night: Precipitation 2-8mm, ridgetop wind: strong S-SWSunday: Precipitation 1-3mm, freezing level am: 1200m pm: 1600m, ridgetop wind: moderate-strong SE-SWSun. Night/Monday: Precipitation 2-5mm, freezing level am: 1100m pm: 1500m, ridgetop wind: moderate-strong S-SW decreasing to light SE-S

Avalanche Summary

No new avalanches have been reported but this may be due to a lack of observers in the field.

Snowpack Summary

The new snow may sit on a melt-freeze crust, old wind slabs in leeward features, or dry snow in sheltered north facing terrain at higher elevations. Recent strong S through W winds have created wind slabs in leeward features. In some areas, there may still be a weak layer below the old storm snow, down roughly 50-80cm, but triggering of this layer has become stubborn or unlikely. Cornices are also large and potentially weak, particularly during periods of warming. The early February persistent weak layer is typically down 1.5 to 2m. Triggering of this layer has become unlikely but may still be possible with heavy triggers such as cornice falls or smaller avalanches stepping-down.

Problems

Wind Slabs

Wind slabs are have formed in leeward features from recent snowfall and moderate-strong S-SW winds. Storm slabs may be a concern areas which received higher snowfall amounts.

The new snow will require several days to settle and stabilize.>Avoid freshly wind loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

A deeply buried persistent weak layer still has the potential to produce very large avalanches and could still be triggered by heavy triggers such as cornice falls or smaller avalanches stepping-down.

Exercise caution on steep, unsupported slopes.>Be aware of the potential for large, deep avalanches due to the presence of buried facets and surface hoar.>Conditions have improved, but be mindful that deep instabilities are still present.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

3 - 5

Valid until: Apr 19th, 2014 2:00PM