Avalanche Forecast

Issued: Mar 29th, 2013 4:44PM

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

a.l. horton, Parks Canada

Jasper.

Spring Conditions. Expect the avalanche danger level to rise at all elevations by early afternoon as conditions warm. Travel early! Cornice fall is becoming a greater concern with the warm weather.

Summary

Weather Forecast

The freezing level is expected to rise to above 2500m on Saturday. High cloud and light to moderate west winds are forecasted as well. Slightly cooler temperatures are possible on Sunday.

Snowpack Summary

A 5 to 10 cm melt freeze crust on solar aspects below treeline appears to be maintaining its strength until mid afternoon. Isothermal conditions exist on shallow south facing slopes up to treeline. North facing treeline and the alpine snowpack are relatively stable with a well settled mid-pack bridging basal facets.

Avalanche Summary

The wet loose avalanche cycle continues on steep solar aspects from treeline to valley bottom beginning by mid-afternoon. Slides ranged from 0.5 to large 2 in size.

Confidence

Timing or intensity of solar radiation is uncertain on Saturday

Problems

Loose Wet

Wet slides are beginning on steep rocky slopes by early afternoon as daytime heating and solar radiation breaks down the overnight melt/freeze crust.

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

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

Large triggers such as cornice fall can triggered this weakness. Large avalanches on steep slopes are possible as warm temperatures are expected in the alpine and solar radiation will be intense.

Cornices become weak with daytime heating, so travel early on exposed slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Mar 30th, 2013 4:00PM