Avalanche Forecast Jasper National Park

Date Issued: Valid Until:

Parks Canada jasper snow safety, Parks Canada

Avalanche Forecast

Sun Apr. 28th · 4:44PM

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low
Wind Slabs Wind Slabs
Persistent Slabs Persistent Slabs
Loose Wet Loose Wet

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low

Alpine

Danger Ratings Considerable

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low

Cool temperatures are expected to preserve problems for a few days until the new snow has had time to settle.

Weather Forecast

Monday will be clouds, sun, and flurries, trace of snow, treeline -5C, light winds, and 1500m freezing level. Tuesday will be similar, low -8 and high -5C, light winds, and freezing level 1700m. Wednesday may bring 7cm of snow.

Snowpack Summary

15cm of snow on Friday in the Icefields, the same Saturday at Maligne from an upslope storm. The snow was reverse loaded by Strong N-NE winds and overlies several crusts/facet layers in the upper snowpack. Stubborn windslabs can be expected on most aspects in the alpine and treeline. A faceted midpack layer on shady alpine slopes remains a concern.

Avalanche Summary

Good visibility at Maligne range observed one recent size 2.5 persistent slab in an alpine bowl, E aspect, convex shaped terrain, likely initiated by morning sun. No other activity was noted but the patrol was before noon. No new activity was noted on an icefields parkway road patrol.

Confidence

Due to the number and quality of field observations

Problems

Wind Slabs

Wind Slabs

Saturday night's strong N winds and snowfall (higher amounts in the front ranges) has built fresh slabs on S aspects.  Older windslabs exist on N aspects, and may be bonded by now.

  • Use caution in lee areas. Recent wind loading has created wind slabs.
  • Keep an eye out for reverse loading created by N-NE winds.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2
Persistent Slabs

Persistent Slabs

Sensitivity of this layer may have increased on slopes loaded by recent wind and snow. Crusts in upper snowpack and deeper facet layers warrant further investigation.

  • If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
  • Watch for signs of instability such as recent avalanche activity, and whumpfing/cracking underfoot.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 3
Loose Wet

Loose Wet

Activity could increase with presence of intense sun particularly on steep Southerly aspects.

  • If the sun stays out you should avoid steep South and West aspects this afternoon.

Aspects: South, South West.

Elevations: Alpine, Treeline.

Likelihood

Possible - Unlikely

Expected Size

1 - 2