Avalanche Forecast

Issued: May 2nd, 2018 4:00PM

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, Wet Slabs and Cornices.

Parks Canada ian jackson, Parks Canada

This is the last scheduled avalanche bulletin for the season. Above average snowpack at high elevations means we should have an extended spring ski season! Check out the Mountain Conditions Report weekly regional summaries for up to date conditions.

Summary

Weather Forecast

Some helpful weather links:Remote weather stations in Banff, Yoho & Kootenay - Real time, raw, actual weather data.Avalanche Canada Mountain Weather Forecast - Good for getting an overview of the major weather systems.SpotWx - Good for a localized forecastEnvironment Canada Yoho forecast - Simplified valley bottom forecast for Lake Louise area.

Snowpack Summary

Isothermal snow exists at lower elevations. Crusts formed during clear cool nights will break down quickly with solar inputs and daytime warming. Expect moist surface snow to mountain top in the afternoon with the exception of high elevation north slopes. Buried weak layers persist at treeline and above and will become reactive as temperatures warm

Avalanche Summary

In general, avalanche hazard will be greatest during hot sunny days or warm rain. This has the potential to trigger smaller loose wet avalanches and larger wet slab avalanches on the basal weak layer. For current avalanche activity and observations, check out the Mountain Conditions Report

Confidence

Problems

Loose Wet

An icon showing Loose Wet
Warm temperatures or rain will rapidly increase the likelihood of loose wet avalanches at all elevations. Pay close attention to the integrity of surface crusts and avoid traveling in avalanche terrain once the crusts have broken down.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Wet Slabs

An icon showing Wet Slabs
New snow, intense heating or large triggers could initiate wet slabs in steep terrain, possibly stepping down to deeper weak layers in the snow pack. Avoid exposure to steep slopes if the snow is becoming moist or wet.
Travel early before the heat of the day melts surface crusts, and avoid big slopes in the afternoon.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Cornices

An icon showing Cornices
Cornice failures are occurring on a regular basis with warm temperatures, new loading or intense solar inputs. In some places these large triggers have also caused failures on the deeper weak layers in the snow pack pulling out larger slabs.
Minimize exposure to overhead hazard from cornices.Cornices become weak with daytime heating, so travel early on exposed slopes.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: May 3rd, 2018 4:00PM