Avalanche Forecast

Issued: Mar 25th, 2013 4:35PM

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

conrad janzen, Parks Canada

Waterton Lakes.

Excellent skiing on E and W aspects in the Forum/Wall Lakes areas today! Watch for isolated wind slabs in steep alpine terrain and keep an eye on daytime temperatures. Rising temperatures will increase the hazard from cornices and loose wet slides.

Summary

Weather Forecast

A stable weather pattern with clear skies and light W winds will persist for the next several days. Daytime temperatures will slowly rise each day with freezing levels forecast to reach 2200m on Thursday. Overnight temperatures remain cool. No precipitation is expected.

Snowpack Summary

Sun crust forming on SE to SW aspects. E and W aspects still providing excellent skiing today! Light wind effect in open areas at tree line and above and some small wind slabs present near ridge crests. 15 to 40cm of recent storm snow bonding well to the crust below.

Avalanche Summary

Very little avalanche activity over the last several days. Some sluffing in very steep terrain. Cornice failures remain a concern especially with mild daytime temperatures.

Confidence

Problems

Wind Slabs

Wind slabs may be present in isolated locations at tree line and above. In most places these wind slabs are bonding well to the surfaces below but assess this bond carefully before entering steep or committing terrain.

Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Cornices

With mild temperatures forecast we may see cornice failures over the next several days. These are large triggers and have the potential to create larger avalanches. Minimize your exposure to slopes with cornice hazard, especially when it is warm.

Cornices become weak with daytime heating, so travel early on exposed slopes.Pay attention to overhead hazards like cornices.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Loose Wet

As the daytime temperatures rise we may see loose wet avalanches on steep solar aspects especially if dark objects like rocks and trees are present on the slopes. Travel early on steep solar aspects and pay close attention to daytime temperatures.

Watch for clues, like sluffing off of cliffs, that the snowpack is warming up. Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

Aspects: North, North East, East.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 28th, 2013 4:00PM