Avalanche Forecast

Issued: Nov 23rd, 2016 3:53PM

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

cam_c, Avalanche Canada

Purcells.

Danger is expected to increase with forecast snow and wind. As always, and especially when forecast confidence is low, it's important to supplement this forecast with your own observations. Please post your obs to the MIN.

Summary

Confidence

Weather Forecast

Light snowfall is expected for Thursday and Friday with 5-10cm of accumulation each day accompanied by moderate to strong southwesterly alpine winds and freezing levels at valley bottoms. Snowfall and winds should ease off with a clearing and cooling trend for Saturday.

Avalanche Summary

Recent reports include a natural Size 2 storm slab avalanche on a steep fan below a large alpine face in the Glacier Creek area. Check out the MIN report for for details including a photo.

Snowpack Summary

Recent reports suggest average snowpack depth is 80-150cm in the alpine and 60-100cm at treeline. The snowpack below treeline remains below threshold for avalanches, but watch out for early season hazards such as hidden rocks, stumps, and open creeks. Up to 40cm of recent storm snow is settling into a cohesive slab over a hard crust. This crust is the primary weakness of concern and is expected to become increasingly reactive as the slab above settles and stiffens. Southerly winds have also formed very touchy wind slabs on lee features below ridetops in exposed terrain. Although conditions have been reported as being quite good, remember that an early season snowpack is inherently weak and requires thorough investigation before stepping out into bigger terrain.

Problems

Wind Slabs

Touchy fresh wind slabs are primed for triggering on the downwind side of ridgecrests in exposed areas.

Travel on ridgetops to avoid wind slabs on slopes below.Avoid areas where the snow feels stiff or 'slabby'.Avoid steep or convex lee features directly below ridgetops.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Storm Slabs

Recent storm snow is beginning to settle into a cohesive slab that may be bonding poorly to a hard crust. On steep slopes the powder may also be sluffing readily.

Be cautious of sluffing in steep terrain.Carefully assess the bond to the crust before committing to a slope.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Nov 24th, 2016 2:00PM