Avalanche Forecast

Issued: Mar 8th, 2016 4:00PM

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

garth lemke, Parks Canada

Jasper.

The Icefields area appears to be more stable than Maligne and Whistler creek areas. Whumphing, remote triggering, and shooting cracks are occurring in these zones.

Summary

Weather Forecast

Wednesday will be cloudy, seasonal temperatures, and 1500m freezing level . A storm may bring 30mm of precipitation, strong winds, and rising freezing levels Wednesday evening into Friday morning. Likely rain lower elevations. Models are not agreeing but if this transpires,Â this will be a significant change.Â

Snowpack Summary

Variable snow depth above treeline. Expect wind slabs in lee and cross-loaded terrain above 2000m. The persistent slab is down 40-90cm. It is touchy in the Whistler/Portal areas even on low angle slopes but is stubborn in the Icefields with inconsistent stability test results. Lower elevation snowpack is facetted and weak.

Avalanche Summary

Tuesday's field patrol in the Icefields observed no new avalanches with good visibility. Previous reports of remotely triggered avalanches to size 2 on slope angles as little as 15 deg around Marmot Pass with whumphing and cracking. Whumphing also noted in the Maligne area. In contrast, no reports of any propagations in the Icefields area.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Thursday

Problems

Persistent Slabs

This problem is very active in the Whistler/Portal Creek area with remotely triggered avalanches being reported on very low angle terrain. The problem is also active in the Maligne area but is stubborn in the Icefields area.

Remote triggering is a concern, watch out for adjacent slopes.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Expect slab development immediate to lee ridge lines and cross loaded features. Bonding should be good but progress cautiously into steeper terrain.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Mar 9th, 2016 4:00PM