Avalanche Forecast

Issued: Mar 22nd, 2016 8:07AM

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

ian gale, Parks Canada

Glacier.

Pay attention to daytime heating. Windslabs and cornices will become more reactive as temperature increases

Summary

Weather Forecast

Clear this morning with increasing cloud in the afternoon as pacific front moves inland. Freezing levels are forecasted to reach 1700m today with an alpine high of -2 deg and variable ridgetop wind gusting to 25kph. Starting tonight(Tues) through Thursday up to 20 cm of new snow is forecast.

Snowpack Summary

We experienced a good overnight freeze last night, and the snowpack should be crusted over to 2000m. Windslab exists on alpine lee features. Last week's storm snow is well settled with the warm temps and sits over crusts on solar aspects. The Feb 27 interface is down 70cm and is more sensitive on steep solar aspects.

Avalanche Summary

Over the weekend there was a number of avalanches triggered by cornice fall. Monday's warm temps triggered a natural avalanche cycle to sz 2.5, with avalanches leaving moist deposits. Freezing levels have dropped significantly which has improved avalanche hazard at treeline & below

Confidence

Due to the number of field observations

Problems

Wind Slabs

Previous SW winds have created soft slabs in the alpine and promoted rapid cornice growth. Cornice failure has the potential to trigger deeper layers in the snowpack. Avoid spending time underneath these beasts & give a wide berth on ridges.

Use caution in lee areas. Recent wind loading have created wind slabs.Pay attention to overhead hazards like cornices.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Buried crusts and associated weak layers have created persistent instabilities on solar aspects. Recent storm snow sits on top of crusts 30-50cm down. Feb 27 interface down 80-120cm still producing sudden planar results. Take the time to evaluate.

Be aware of thin areas that may propogate to deeper instabilites.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Mar 23rd, 2016 8:00AM