Avalanche Forecast

Issued: Mar 29th, 2015 9:02AM

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

pgoddard, Avalanche Canada

Purcells.

Direct sun is possible in some areas on Monday and may spark a new avalanche cycle in steep terrain.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain

Weather Forecast

Snow eases to flurries on Monday, then the next pulse begins on Monday night, bringing around 5-10 cm snow with moderate to strong SW to NW winds. A few flurries or convective showers may continue on Tuesday. Freezing levels are around 2000 m, dropping by late Tuesday to around 1200 m. Â

Avalanche Summary

On Thursday and Friday, wind and warming were responsible for several natural slab avalanches up to size 3, mainly on east and north aspects above 2100 m. There was also a report of a close call, skier triggered size 2.5 slab avalanche in the Dogtooth range. A couple of small slabs were triggered on Saturday.

Snowpack Summary

New snow fell to around 1900-2100 m on Saturday, with rain at lower levels. Strong winds have formed wind slabs on lee slopes. The mid-March interface (crusts, old wind slabs, facets and surface hoar) is down around 60 cm. In snowpack tests, it is still giving moderate to heard, sudden results with propagation likely. The deeper mid-February layer has been dormant for some time; however in neighboring regions it has been reactive. Persistent weak layers may be suspect in shallower snowpack areas.

Problems

Storm Slabs

New snow and winds are likely to create touchy storm slabs, especially on features in the lee of the wind. A storm slab could fail on a deeply buried weakness, creating a surprisingly large avalanche.

Avoid freshly wind loaded features.>Choose well supported terrain without convexities.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Mar 30th, 2015 2:00PM