Avalanche Forecast

Issued: Feb 16th, 2016 5:06PM

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

Ruari Macfarlane, Parks Canada

Waterton Lakes.

Breakable, and semi-breakable crust dominates Below Treeline, and on all sunny slopes, sitting above punchy, moist snow. Higher up, modest amounts of recent snow, falling with SW winds, have created both wind slabs, and reasonable skiing.

Summary

Weather Forecast

On Wednesday, the Freezing Level rises to at least Treeline, with occasional flurries/showers. Thursday/Friday look cloudy, with temperatures cooling steadily. Several forecasts predict 5-10 cm of new snow falling on Thursday. Wednesdays' wind will be Moderate from the SW, rising through Thursday / Friday to Strong or Extreme from the SW.

Snowpack Summary

25mm of precipitation with strong SW wind over the weekend left a rain crust and moist/punchy snow below 2200m, and built 20-30cm thick wind slabs on lee slopes at Treeline and Alpine elevations. Another crust buried 40cm deep at treeline produced hard, but sudden, results in snowpack tests on Tuesday. Surface crusts exist on sunny aspect slopes.

Avalanche Summary

A Size 1.5 naturally triggered avalanche was observed to have occurred near Cameron Lake on Tuesday. This started in steep, un-skiable, NE aspect Alpine terrain.

Confidence

Forecast snowfall amounts are uncertain on Thursday

Problems

Wind Slabs

At Treeline, wind slabs exist on the North and East sides of ridge crests. In open and Alpine terrain, their distribution is more random. Although the Wind Slabs feel stubborn to human triggers, be aware of a crust down 40cm that these could fail on.

Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 19th, 2016 4:00PM