Avalanche Forecast

Issued: Apr 13th, 2015 4:00PM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs, Loose Wet and Cornices.

tim haggarty, Parks Canada

Waterton Lakes.

Forecast cooling and a bit more snow on Tuesday should keep winter alive at upper elevations for a few days yet...

Summary

Weather Forecast

After freezing levels went over 2600m Monday, a limited recovery is expected. An expected 15mm of precip will start in the morning falling as snow above 1800m and lowering as a cold front passes late in the day. Wednesday should remain cool with winds out of the North before temperatures start to climb again on Thursday with mainly sunny skies.

Snowpack Summary

10cm of snow fell over the weekend and moderate W winds created widespread wind slabs Treeline and above. This snow sits on a solid crust found everywhere but above 2400m on N aspects. Strong heating today created new surface crust on all but the highest N aspects and widespread loose dry and wet activity has affected snow surfaces.

Avalanche Summary

With the snow over the weekend there was a limited cycle of loose dry avalanches out of steep shaded terrain. With strong heating today widespread loose wet and a limited amount of wet slab activity was seen as the storm snow failed over the previous crusts.

Confidence

Intensity of incoming weather systems is uncertain on Tuesday

Problems

Wind Slabs

New snow Tuesday will add to slabs that can be found in the highest north facing terrain.

Use caution in lee areas in the alpine and treeline. Recent storm snow has formed touchy slabs.The new snow will require several days to settle and stabilize.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Loose Wet

As the sun comes out on Thursday, expect the new snow to fail easily over the crusts.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Cornices

Cornices are large and are susceptible to the powerful solar heating at this time of year. A falling cornice can create a large avalanche on the slope it hits giving them surprising reach in their destructive potential.

Cornices become weak with daytime heating. Pay attention to overhead hazards like cornices.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Apr 14th, 2015 4:00PM