Avalanche Forecast

Issued: Feb 19th, 2019 4:00PM

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

jasper snow safety, Parks Canada

Jasper.

Manage your exposure and keep wary to evidence of localized instability such as cracking, whumphing and, recent avalanche activity.

Summary

Weather Forecast

Wednesday will be mix of sun and clouds with isolated flurries, alpine temperature high -11 C, and West 10-20 km/h winds. Thursday will be sun with clouds, no snow, alpine temperature low -21 C and high -13 C, West 10 km/h winds. A detailed mountain weather forecast is available from Avalanche Canada.

Snowpack Summary

The upper snowpack is faceted creating a weak slab over a instability of surface hoar/facets on a crust down 40cm. The thicker snowpack spots have a strong mid-pack bridging the deep persistent basal weakness of depth hoar. Thinner snow-pack zones are much less consolidated and can act as a slab triggering the basal depth hoar.

Avalanche Summary

Tuesday's patrol was poor visibility but several loose dry avalanches up to size 1 were noted in steep rocky terrain. We could not see into the alpine nor beyond the trees along the roadside. Saturday's field team into Whistler Creek reported no new avalanches.

Confidence

Problems

Deep Persistent Slabs

It is possible to trigger deep slabs in shallow snowpack areas. Terrain management and assessment is critical to a safe day.

Be cautious in shallow snowpack areas where triggering is more likely.Minimize exposure to terrain traps where the consequences of an avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 3

Loose Dry

Sun may act as a trigger to initiate the loose unconsolidated surface snow particularly in steep rocky terrain. Definitely a problem ice climbers should keep on radar where small slides can gain mass particularly in terrain traps.

Be careful of loose dry power sluffing in steep terrain..If triggered dry loose point releases can form deeper deposits in terrain traps.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 20th, 2019 4:00PM