Avalanche Forecast

Issued: Feb 26th, 2016 4:00PM

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

a.l. horton, Parks Canada

Jasper.

Snow and SW wind on Saturday will be building new windslab conditions. Stick to sheltered slopes for best conditions.

Summary

Weather Forecast

The freezing level is only expected to drop to 1500 m overnight on Friday with possibility of heavy snow and moderate SW winds.Â Snow to continue through Saturday.Â Expecting a good recovery on Saturday night and light precipitation beginning Sunday night into the new week.

Snowpack Summary

Warm temps are developing isothermal conditions below tree-line and on solar aspects into tree-line.Â A persistent slab is bridging weak depth hoar at most tree-line locations.Â This slab will lose its support as temperatures rise and if overloaded by new snow.Â Thin rocky solar exposed alpine slopes are beginning to shed.

Avalanche Summary

No field trips on Friday. A large cornice triggered sz 3 slab avalanche on cross-loaded alpine NW facing slope was reported in the Icefields on Thursday.Â Numerous loose wet avalanches to sz 2 were observed in Portal Creek on Friday as sun heated the alpine slopes.

Confidence

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

Problems

Wind Slabs

The new snow will becoming in warm with good transport winds from the SW. Excellent slab forming conditions on lee slopes. Bonding should be good but best to avoid steep terrain.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Avoid steep lee and cross-loaded slopes

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Persistent weak layers of decomposed surface hoar, facets, and depth hoar are in many locations. These layers have been stubborn to trigger underfoot but could be triggered by cornice failure or from shallow spot.

Carefully evaluate terrain features by digging and testing on adjacent, safe slopes. Avoid steep slopes below cornices.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 27th, 2016 4:00PM