Avalanche Forecast

Issued: Apr 29th, 2014 4:40PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is high. Known problems include Loose Wet, Deep Persistent Slabs and Cornices.

max darrah, Parks Canada

Jasper.

SIGNIFICANT WARMING TREND over the next 48 hours with freezing levels rising to 3500m and staying there (ie. poor overnight freeze) until Friday. Keep an eye on the temperatures and plan to be out of avalanche terrain early in the day.

Summary

Weather Forecast

SIGNIFICANT WARMING TREND over the next 48 hours with freezing levels rising to 3500m and staying there (i.e. poor overnight freeze) until Friday. Over the weekend we expect cooler temps and a shift to a North Easterly flow which has the potential to bring up to 10mm of precipitation falling as rain below 2300m.Â

Snowpack Summary

There is rain crust from the valley bottom to 2,350m and a sun crust into Alpine on solar aspects.Â We expect a widespread natural avalanche cycle over the next 48 hours as temperatures rise and the crusts deteriorate.Â This has the potential to produce large, full depth avalanches on all aspects.

Avalanche Summary

Several loose wet size 2 noted on Mt sask at 2100-2500m stopping before the river. One size 2 loose wet off boundary peak. Cornice failure peak across sunwapta station E aspect initiated nothing. Isolated loose wet activity in the Maligne Valley on solar aspects.

Confidence

Timing or intensity of solar radiation is uncertain

Problems

Loose Wet

Expect loose wet avalanches as we receive the warmest temperatures of the spring over the next 48 hours.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

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

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Deep Persistent Slabs

Full depth avalanches are probable over the next 48 hours as the snowpack becomes weaker with rapid warming. Cornices may trigger deeper instabilities.

Pay attention to overhead hazards like cornices.Be aware of the potential for full depth avalanches due to weak layers at the base of the snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Cornices

Cornices are big and looming and will weaken significantly over the next 3 days.

Do not travel on slopes that are exposed to cornices overhead.Cornices become weak with daytime heating.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Apr 30th, 2014 4:00PM