Avalanche Forecast

Issued: Apr 20th, 2015 4:09PM

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 and Cornices.

brian webster, Parks Canada

Banff Yoho Kootenay.

Only a light freeze is forecasted for Monday night, followed by a very warm day on Tuesday. Pay attention to how quickly the snow is warming up.

Summary

Weather Forecast

Tuesday will be mainly sunny withÂ light winds and freezing levels rising up to 2900 m. Wednesday will be slightly cooler with the potential for some scattered showers.

Snowpack Summary

Supportive crust on solar aspects in morning which are deteriorating by early afternoon. High elevation east and north still have dry snow. Mid pack is well settled with no significant shears. The basal facets remain the main weakness in the snowpack, but we expect only large loads or a dramatic rise in temperatures to cause failures on this layer.

Avalanche Summary

Loose snow avalanches up to size 1.5 on solar aspects in afternoon.

Confidence

Problems

Loose Wet

Expect solar triggered avalanche activity on steep solar aspects in the afternoon. It is possible that wet slides could trigger the basal facet layers if they have enough mass. Start early and be off steep solar aspects by midday.

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: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Cornices

The forecasted warm/hot temperatures midweek will create a situation where cornices are more unstable. Cornices, combined with the hot temperatures, have the possibility to triggering the deep basal layers.

Extra caution needed around cornices with current conditions.Cornices become weak with daytime heating, so travel early on exposed slopes.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Apr 21st, 2015 4:00PM