Avalanche Forecast

Issued: Mar 29th, 2016 4:00PM

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

garth lemke, Parks Canada

Jasper.

Warm temperatures are starting to wake up the avalanche problems particularly when the afternoons are warm. Start and end your day early. Some avalanches are running quite far.

Summary

Weather Forecast

Tuesday night freezing level will be 1200m rising to 2500m on Wednesday with variable clouds and light N winds. No overnight freeze Wednesday night and sun and very warm temperatures and sun Thursday and Friday. Thursday night may have a light freeze.

Snowpack Summary

Cold overnight temps and warming by midday is creating spring like snowpack and surface crusts. Significant variation in snowpack depth through-out the forecast area but generally shallow and below threshold in valley bottoms. Weak basal depth hoar exists. Maligne/Whistler creek areas have less coverage.

Avalanche Summary

Some wet slides on solar aspects in the south end of the park occurring below treeline. Several size 2's and a couple size 3's on a variety of aspects mainly in alpine noted Tuesday, related to steep slopes, shallow locations, rocks, cornice failures, and loose avalanches triggering slabs below.Â

Confidence

Timing or intensity of solar radiation is uncertain on Wednesday

Problems

Deep Persistent Slabs

This problem is becoming more active. When triggered, it will be big with serious consequences. Warm and sunny conditions will increase this danger. Steep sun facing rocks, cornice failures, and loose avalanches from above are waking up this problem.

Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Cornices

Increase occurrence of cornice failures are being noted. It can act as a large trigger initiating deep weaknesses plus their sheer mass, whether or not it initiates an avalanche, would be like being hit by a car.

Cornices become weak with daytime heating. Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Loose Wet

This problem will increase with forecasted warm temps and intense solar radiation. The danger rating will rapidly increase particularly on thin snowpack zones and sun facing slopes. Loose avalanches can initiate larger avalanches below.

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

Unlikely - Possible

Expected Size

1 - 2

Valid until: Mar 30th, 2016 4:00PM