Avalanche Forecast

Issued: Apr 26th, 2017 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is considerable. Known problems include Loose Wet, Cornices and Deep Persistent Slabs.

A.L. Horton, Parks Canada

Jasper.

Steady rain on Thursday will increase the avalanche hazard below tree-line.

Summary

Weather Forecast

15 cm of snow is expected above tree-line by late Thursday afternoon. This snow will come in with light W winds that will shift to North. The freezing level will rise to 2000 m Thursday. Snow will continue into Saturday with 25 cm total.

Snowpack Summary

20 cm of loose new snow sits over a melt freeze crust in many locations above tree line. The mid-pack is consolidated and bridges the weak base. The bottom snowpack is a mix of weak facets and depth hoar.

Avalanche Summary

Some small solar point releases noted out of rocky areas today.

Confidence

Forecast snowfall amounts are uncertain on Thursday

Problems

Loose Wet

Rain (5-20 mm) possible on Thursday will increase this problem below tree-line.

Avoid avalanche terrain during periods of heavy loading from new snow, wind, or rain.

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 2

Cornices

Cornice failures are still being noted periodically on West aspects 2500-2800m.

Give cornices a wide berth when travelling on or below ridges.Avoid travel on slopes that are exposed to cornices overhead.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Deep Persistent Slabs

The deep instability could be triggered by a cornice failure. It is well bridged by a solid mid-pack.

Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Apr 27th, 2017 4:00PM