Avalanche Forecast

Issued: Feb 7th, 2012 9:01AM

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

Avalanche Canada swerner, Avalanche Canada

Summary

Confidence

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

Weather Forecast

The weather patterns will start to change on Wednesday. The South Coast will see light amounts of precipitation starting in the afternoon with freezing levels near 1000m. They could rise to 1500m later in the afternoon. Thursday into Friday may bring light-moderate (up to 20mm) precipitation, with freezing levels rising to 1300m. Ridgetop winds will be moderate from the SE, switching Southerly towards the end of the forecast period. Weather models disagree; confidence in precipitation amounts is poor.

Avalanche Summary

No new avalanche observations reported today.

Snowpack Summary

Surface snow conditions consist mainly of crusts that have developed due to melt/freeze conditions, and direct solar impact on steep Southerly aspects. Northerly aspects still host dry, wintery snow. On lee slopes in the alpine there are pencil-4 finger hard wind slabs. Surface faceting is occurring on sheltered, shady aspects. While shallow, rocky slopes are faceting and weaker; posing a threat to deeper releases. Surface hoar development up to 5mm has been reported at treeline, and below treeline. These may be our next layers of concern once buried. The Feb 01 (120201) rain crust is down 10-40 cm up to about 2000 meters. The mid-January crust is down between 50-100 cm, and the mid December crust is buried down up to 200 cm. The average snowpack depth at 1650m is near 240cm.

Problems

Cornices

An icon showing Cornices
Cornices may become weak with daytime warming, and solar radiation. Cornice fall may trigger slabs on the slopes below. Give cornices a wide berth when traveling on ridgetop, or on slopes below.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

2 - 6

Wind Slabs

An icon showing Wind Slabs
Strong SE ridgetop winds may have created wind slabs on lee aspects in the alpine.

Aspects: North, North East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 8th, 2012 3:00AM