Avalanche Forecast

Issued: Jan 8th, 2013 4:00PM

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

A.L. Horton, Parks Canada

Jasper.

A large storm with heavy snow is moving in from the Pacific. Southern portions of the forecast area could receive a substantial snowfall. Avalanche conditions will move to High if this occurs.

Summary

Weather Forecast

A fast moving low pressure system will bring up to 30 cm of snow Tuesday night through to Wednesday evening. Over 60 cm of snow is possible in southern portions of the forecast area. Strong SW alpine winds will accompany the onset of this storm that will ease to light northerlies by the end of the day.

Snowpack Summary

Widespread surface hoar (2-7mm) has been buried by up to 10 cm of new snow. The snowpack is faceted and is losing strength in shallow areas. The mid-pack is supportive where the snow depth is greater than a meter. Wind slabs are present in lee features at tree line and above.

Avalanche Summary

No new avalanches were seen in the Icefields area today.

Confidence

Forecast snowfall amounts are uncertain on Wednesday

Problems

Wind Slabs

New wind slabs will be forming on lee slopes with 30 cm of storm snow and strong SW alpine winds. Open tree line features will also see slab development. In many lee areas, these slabs will be sitting on top of the weak January 6th surface hoar.

Avoid freshly wind loaded features.Make observations and assess conditions continually as you travel.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 3

Storm Slabs

Up to 30 cm of storm snow is possible in the next 24 hrs. We will likely see an avalanche cycle involving the storm snow on steep slopes.

Watch for terrain traps where small amounts of snow will acumulate into deep deposits.Avoid ice climbs that are in terrain traps below large start zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 3

Valid until: Jan 9th, 2013 4:00PM