Avalanche Forecast

Issued: Apr 5th, 2013 4:19PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Storm Slabs, Cornices and Loose Wet.

mike eder, Parks Canada

Jasper.

Monitor the weather changes throughout the day. Modify your travel routes if any significant elements of weather occur, such as extended sunny periods or heaven forbid, rain.

Summary

Weather Forecast

Light to moderate snow flurries are expected to continue through the day on Saturday as a cold front moves through the area. Winds will gust to moderate from the Southwest in the late afternoon followed by a drop in temperature into the evening. Sunday will return to no snowfall and high diurnal temperature variations through the day.

Snowpack Summary

Below Treeline a supportive 15cm melt freeze crust provides temporary stability above a wet and unconsolidated snowpack. The crust thins with elevation and on slopes which are not South facing. By mid afternoon, or earlier on very hot days, this crust will melt and the avalanche danger will elevate considerably. The base of the snowpack is weak.

Avalanche Summary

Today, several loose avalanches were observed with the new snow, from steep rock cliffs. Alpine and treeline locations were not visible in the icefields area. Steep, Southerly aspects below 1600m are mostly melted out.

Confidence

Forecast snowfall amounts are uncertain on Saturday

Problems

Storm Slabs

Additional snow coming overnight may provide the load to start a slide on this layer. Slab bonding is expected to be touchy on the current sun and temperature crusts. Expect to see this type of activity in steep rock gullies.

Avoid freshly wind loaded features.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

These heavy and unstable features can fall unexpectedly triggering deep large avalanches. Pay attention to overhead hazards when selecting your up track and your descent route.

Avoid steep slopes below cornices.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Loose Wet

If sunny, pay close attention to the increasing air temperature and the thickness of the melt freeze crust. Rain events will increase the elevation, range and aspect of this hazard.

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

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 6th, 2013 4:00PM