Avalanche Forecast

Issued: Mar 30th, 2013 4:00PM

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.

Travel early in the day to take advantage of the supportive melt freeze crust and be off solar slopes by mid-day. Good ski conditions can be found on sheltered north facing treeline aspects

Summary

Weather Forecast

High cloud will be accompanied by light NW winds. The freezing level is again expected to reach 2500m 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. A large (size 3) slab avalanche on a steep rocky west facing alpine slope ran full path to ground across from the Parker Slabs, likely a solar trigger. The alpine is waking up on south to west aspects!

Confidence

The weather pattern is stable on Sunday

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 on polar 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.

Cornices become weak with daytime heating, so travel early on exposed slopes.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Mar 31st, 2013 4:00PM