Avalanche Forecast

Issued: Apr 2nd, 2015 6:42PM

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.

Cooling has established supportive crusts to treeline. West winds have quickly created windslabs with small amounts of recent snow. Solar heating will be a factor.

Summary

Weather Forecast

Friday will bring sunny breaks with light to moderate winds west winds and a freezing level of 1900m. Saturday should be much the same with a freezing level at 1800m. More cooling can be expected for Sunday and Monday with flurries producing up to 15cm of snow.

Snowpack Summary

The entire snowpack was moist BTL and to ridgelines on solar aspects while on shaded aspects the top meter of snow was moist to treeline. With cooling over the last two days a solid crust has formed as the top 10 to 30cm has refrozen in these areas. A thin rain crust exists as high as 2400m on the shaded aspects. 5cm of new snow sits on all of this

Avalanche Summary

With the cooling over the last two days, slab activity has diminished however today loose moist activity was occurring with solar heating and loose dry activity could be seen on the shaded aspects as the new snow failed over the surface crusts to size 1.

Confidence

Problems

Wind Slabs

Soft slabs up to 30cm deep have formed over the crusts with the recent snow. Although thin in many areas, there are some significant slabs that have grown along the ridge crests.

Use caution in lee areas in the alpine and treeline. Recent storm snow has formed touchy slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Loose Wet

Small amounts of snow above the crusts will fail easily with solar heating.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Travel early before the heat of the day, and avoid big slopes in the afternoon.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

The recent growth that has developed on the cornices is quite fragile. With heating or continued wind this new growth may fail and would likely trigger windslabs on the loaded slopes below.

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

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 5th, 2015 4:00PM