Avalanche Forecast Jasper National Park

Date Issued: Valid Until:

Parks Canada timothy johnson, Parks Canada

Avalanche Forecast

Sun May. 12th ยท 4:00PM

Alpine

Danger Ratings High

Treeline

Danger Ratings Considerable

Below Treeline

Danger Ratings Considerable
Loose Wet Loose Wet
Persistent Slabs Persistent Slabs
Cornices Cornices

Alpine

Danger Ratings Considerable

Treeline

Danger Ratings Considerable

Below Treeline

Danger Ratings Moderate

Alpine

Danger Ratings Considerable

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Moderate

Deep avalanche problems are waking-up with warm temperatures resulting in numerous large avalanches. If you go exploring the alpine make sure there has been a good overnight freeze and be out of avalanche terrain before the heat of the day.

Weather Forecast

For Parker Ridge Area

Monday: Cloudy with sunny periods. Treeline temperature: High 9 C. Light ridge wind. Freezing level: 3000 metres.

Tuesday: Showers. Precipitation: 9 mm. Treeline temperature: Low 1 C, High 7 C. Ridge wind southwest: 15-35 km/h. Freezing level: 2800 metres.

Wednesday: Cloudy with sunny periods and isolated wet flurries.

Snowpack Summary

Where snow still exists below treeline, expect slush. At treeline there is still snow on shady aspects but quickly becoming slushy during the day. In the alpine a fresh dusting of snow is being moved around by SW winds and crusts and other deep persistent slab problems are resulting in avalanches due to daytime heat and minimal refreezes overnight.

Avalanche Summary

Since the warming trend started on Friday there has been a widespread avalanche cycle. Numerous loose wet avalanches up to size 2 in the alpine and treeline. Several slab avalanches and cornice failures to size 3.5 have been observed in the alpine on all aspects but predominantly on NE to NW aspects .

Confidence

Freezing levels are uncertain

Problems

Loose Wet

Loose Wet

Summer like temps have created an avalanche cycle. With minimal overnight freezes and more sunny days forecasted this problem will continue for the next while. Limited snow below treeline but one could expect it to be very isothermal and reactive.

  • If triggered loose wet sluffs may step down to deeper layers resulting in larger avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely - Likely

Expected Size

1 - 2
Persistent Slabs

Persistent Slabs

Weak mid-pack facets and upper-snowpack are reactive, especially on shaded, northerly slopes. This is a Wet Slab problem on solar aspects, as water accumulates above strong crusts.

  • If off-trail travel is deep and punchy, avoid all avalanche terrain, including runouts.
  • Minimize exposure to big slopes, especially during the heat of the day.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1.5 - 3
Cornices

Cornices

Occasional cornice falls are expected, some of these may trigger large slab avalanches, running well down into lower elevations.

  • Minimize exposure to overhead hazard from cornices.
  • Stay well to the windward side of corniced ridges.

Aspects: North, North East, East, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3.5