Avalanche Canada mpeter, Avalanche Canada

Sea to Sky Avalanche Forecast

Mar 26th, 2012 11:00AM

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

Summary

Confidence

Fair - Intensity of incoming weather is uncertain

Weather Forecast

Tuesday: Expect an unsettled day with flurries and southerly winds increasing from light to moderate. Freezing levels could reach 1500m with maximum accumulations of 10cm. Wednesday / Thursday: Continued precipitation under a slight cooling trend. Total accumulations could reach 25cm with consistent moderate southerly winds and freezing levels reaching 800m each afternoon.

Avalanche Summary

Recent avalanche activity includes loose moist sluffs to size 2.0 from daytime warming as well as isolated natural cornice releases to size 2.0. Thin windslabs up to size 1.5 have also been seen.

Snowpack Summary

The recent warm, clear weather has left us with an aggressive melt freeze crust on solar aspects well into the alpine while shady, dead north slopes have grown some small surface hoar and remain powdery. Minor accumulations of new snow now overlie these surfaces. Increasing southerly winds are beginning to build new windslabs in lee locations at ridgecrest. Cornices loom in the alpine and continue to grow under the current conditions. The vast amount of recent storm snow continues to settle and bond while deeper in the snowpack the persistent weakness from mid February remain a lingering concern due to continued sudden planar test results.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible

Expected Size

1 - 4
New windslabs are growing at ridgecrest over the slick melt freeze crust. Some thin windslabs have formed in unusual places from downflow winds associated with the warm temperatures on the weekend.

Aspects:

North, North East, East, South East.

Elevations:

Alpine, Treeline.

Cornices

An icon showing Cornices

Likelihood

Possible

Expected Size

1 - 6
Cornices are very large and may become more fragile with the increased load and wind.

Aspects:

North, North East, East, South East.

Elevations:

Alpine.

Valid until: Mar 27th, 2012 9:00AM