Avalanche Forecast

Issued: Mar 8th, 2013 4:09PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is high. Known problems include Loose Wet, Storm Slabs and Loose Dry.

a.l. horton, Parks Canada

Jasper.

The avalanche hazard will spike in the afternoon with warm temperatures and intense solar radiation. The Maligne Road remains closed , avalanche control planned on Saturday afternoon. A late afternoon closure of the Icefields Parkway is possible.

Summary

Weather Forecast

The freezing level will approach 1800 m on Saturday afternoon with clear skies. Winds will be light from the SW. On Sunday, temperatures will moderate, skies will cloud over and light flurries are possible.

Snowpack Summary

The recent storm snow appears to be bonding well to previous surfaces. Soft slabs are developing below alpine lee ridge lines with gusty moderate SW winds . At lower elevations, this snow is sitting on a weak and faceted midpack. Snow that is plastered to steep rocky terrain will most likely sluff once exposed to the sun for prolonged periods.

Avalanche Summary

Temperatures today remained below freezing, however, several size 1-2 wet snow avalanches were observed on steep south facing slopes below treeline due to intense solar radiation. On Saturday, temperatures will approach double digits with high solar radiation, this will result in a High avalanche danger.

Confidence

Timing or intensity of solar radiation is uncertain on Saturday

Problems

Loose Wet

Solar radiation and warm daytime temperatures will start to melt the new snow and penetrate the snowpack. This will create moist or wet point release avalanches on steep solar aspects at lower elevation to treeline.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Finish ice climbs early in the day before the temperature rises.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 2

Storm Slabs

Soft slabs are beginning to build along alpine ridgelines with moderate SW winds. Otherwise, the storm slabs remain soft in nature as winds have yet to firm them up. Soft slab conditions also exist on gully sidewalls and some large alpine slopes.

Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Loose Dry

As the sun peaks out and warms up the day, loose avalanches with significant mass are occurring with increased frequency. They are initiating out of steep W or S facing high elevation rocks or gullies.

Avoid ice climbs that are exposed to steep rocky terrain on solar aspects.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Mar 9th, 2013 4:00PM