Avalanche Forecast

Issued: Apr 14th, 2016 4:41PM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Loose Wet, Storm Slabs and Cornices.

Ruari Macfarlane, Parks Canada

Waterton Lakes.

Avalanche danger will depend heavily on the amount of snowfall tonight, and freezing levels through the weekend. These vary greatly from forecast to forecast. Evaluate conditions carefully.

Summary

Weather Forecast

New snow falls on Thursday night, with strong NE winds, and the rain-snow line lowering to 1300m -forecasts average about 25cm, but vary widely. Friday: Winds drop, snowfall clears. Freezing level 1500m, rising to 2200. Weekend: Sunny, warm, light W winds. Freezing Level uncertain on Saturday- likely 2000-2500m Saturday, rising above 3000m Sunday.

Snowpack Summary

New snow falls Thursday night, with strong NE winds, giving winter-like avalanche problems on Friday. With rising temperatures through the weekend, snowpack conditions will begin to return to Spring-like. Snowpack glide continues slowly on some slopes, with a few new glide cracks noted.

Avalanche Summary

A large (Size 2) cornice avalanche occurred on Tuesday at Treeline. Some activity is expected within the new snow due Thursday night. Glide Cracks on many slopes confirm the potential for full-depth Wet Slab avalanches. Although unlikely, these would be very large. Avoid these slopes.

Confidence

Problems

Loose Wet

Watch for a cycle of loose wet avalanches in the new snow. Size will be dependant on snowfall amount. On Friday this will mainly be on sunny slopes; heat on Saturday and Sunday may spread this problem to higher/shadier terrain.

The new snow will require several days to settle and stabilize.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Storm Slabs

These will be largest and most widely distributed in the Alpine. in the alpine, and will be especially sensitive when they first receive sun (Friday or Saturday).

Keep an eye out for reverse loading created by an upslope storm.Test slopes before committing to them.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Cornices

Cornices are likely to start failing naturally again with high temperatures through the weekend. Make an extra effort to avoid any overhead exposure to cornices on Sunday.

Minimize exposure to overhead hazard from cornices.Stay well back from cornices.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 2

Valid until: Apr 17th, 2016 4:00PM