Avalanche Forecast

Issued: Jan 16th, 2018 4:00PM

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

garth lemke, Parks Canada

Jasper.

Gusting winds and 10cm pulse of snow Wednesday night into Thursday has potential to increase the hazard. Monitor these effects accordingly.

Summary

Weather Forecast

Wednesday will be cloudy with flurries, 5cm of snow, high of -4, 1600m freezing level, and 20-40km/hr SW winds. Thursday will be flurries and 10cm of snow, -4 to -10, 20 gusting 60 km/hr SW winds. Friday will bring clouds, sun, flurries, trace of new snow, -9 to -11 and 15-35 km/hr SW winds.

Snowpack Summary

10-15cm of snow from Jan 10 has blown into thin slabs TL and above. Although the mid-pack Dec 15 layer is a concern but has not been reactive in test profiles nor has it been linked to any avalanche activity in the Jasper area, we are monitoring it closely. There is a distinct crust (Nov 17) in the lower third of the snowpack.

Avalanche Summary

No patrol on Tuesday and nothing new reported. Yesterday with sun and warm air, a pulse of natural loose dry point releases were observed. They were mostly out of steep, solar facing terrain.

Confidence

Wind effect is extremely variable on Wednesday

Problems

Loose Dry

Natural point release avalanches remain a concern particularly in terrain traps or confined gullies. Surface snow remains loosely consolidated and ripe for entraining snow if initiated. New snow next few days will add to this concern.

Be very cautious with gully features.Use caution above cliffs where small avalanches may have severe consequences.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Wind Slabs

Snow was redistributed into thin, spotty slabs in exposed areas. These slabs sit on freshly buried, weak facets and surface hoar in some areas.

Be careful with wind loaded pockets while approaching and climbing ice routes.Watch for surface cracking and stiffer surface layers of snow.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

Isolated slab avalanches to size 2 were reported by field teams on Monday. They were triggered by loose snow avalanches from the cliffs above and solar input.

Avoid shallow snowpack areas where triggering is more likely.Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Jan 17th, 2018 4:00PM