Avalanche Forecast

Issued: Apr 8th, 2018 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs and Persistent Slabs.

jasper snow safety, Parks Canada

Jasper.

Good skiing is found in the region with winter like conditions.

Summary

Weather Forecast

Monday will be Cloudy with sun and flurries, trace snow, high's of -3, light West winds, and 2000m freezing level. Tuesday will be flurries, possibly 10cm Tuesday into Wednesday, -7 to -1, Light SW winds gusting strong with 2100m freezing level. Wednesday will be sun and cloud, flurries, High -4 C, and light SW winds.

Snowpack Summary

Wind slabs are in open high alpine areas with localized winds. The upper snowpack is a 50 to 80 cm thick slab that bridges three weak layers in the mid-pack. Whumpfing and collapses were noted on the Mt. Kitchener slopes facing the highway last week yet natural activity has tapered off.

Avalanche Summary

Sunday patrol noted very little in fresh natural activity as the sun was kept at bay by cloud cover. Some size 1 moist surface sluffing was noted on steep sun facing gullies when the sun did make a brief appearance.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Wednesday

Problems

Wind Slabs

Pockets of 10-30cm thick windslabs are in high elevation alpine ridgetops and crossloaded gullies. They are generally well bonded but pockets of instability exist. Propagations of 50-100m were noted last week but have subsided.

Use caution on open slopes and convex rolls If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Persistent slabs sit on facets on North aspects and a hard melt-freeze crust on solar aspects. Use a cautious approach and assess the bond at these interfaces before committing to a slope.

Watch for signs of instability such as whumpfing, or cracking.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Apr 9th, 2018 4:00PM