Avalanche Forecast

Issued: Mar 31st, 2013 4:00PM

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

rupert wedgwood, Parks Canada

Jasper.

By early afternoon the avalanche danger will have increased significantly at which time you should plan to be out of all avalanche terrain. Afternoon closures along the Icefield Parkway and Maligne Lake road are possible.

Summary

Weather Forecast

Temperatures are not expected to cool off during the next 24hrs.Â Light westerly winds and lots of sunny periods can be expected. Day time highs of 17 degrees for the town of Jasper. These weather factors in combination will result in the avalanche danger increasing rapidly during the day particularly at lower elevations and on solar facing slopes.

Snowpack Summary

A 5 to 10 cm melt freeze crust on solar aspects below treeline appears to be maintaining its strength until mid afternoon. By this time isothermal conditions can be expected up to treeline on solar facing slopes. The snowpack at treeline and above on Northerly facing slopes has a well settled mid-pack providing bridging strength above basal facets.

Avalanche Summary

Numerous wet loose avalanche size 1-2 are occurring from steep solar aspects fromÂ the valley bottom to 2,300m. Several slab avalanche up to size 2.5 have been observed from the alpine. These areÂ mostly originating below steep rocky terrain. As the snowpack heats up larger events are possible by mid afternoon potentially running full path.

Confidence

Timing or intensity of solar radiation is uncertain

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.

Start and finish early before the surface crusts melt.Extra caution needed around cornices with current conditions.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

Large triggers such as falling cornices can triggered this weakness on solar aspects. Large avalanches on steep south to west slopes are possible as warm temperatures are expected in the alpine and solar radiation will be intense.

Finish ice climbs early in the day before the temperature rises.Travel early before the heat of the day, and avoid big slopes in the afternoon.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Apr 1st, 2013 4:00PM