Avalanche Forecast

Issued: Jan 24th, 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.

deryl kelly, Parks Canada

Jasper.

Forecasted snow (5-8cm) shouldn't be enough to overload persistent weaknesses in the upper snowpack. Due the variable distribution of these layers it would behoove you to keep monitoring the sensitivity of any slope before you commit to riding it!

Summary

Weather Forecast

The incoming storms have mostly blown themselves out by the time they get into the forecast area. For Wednesday, expect as much as 5 to 8cm overnight the through the morning Thursday. Alpine High -6C. Ridge wind light to moderate SW, gusting to moderate values.

Snowpack Summary

Windslab continues to build in open areas and sits above 3 weak interfaces in the top 30 to 50cm of the snowpack. The distribution of these surface hoar/facet layers varies with the terrain, but is most predominant in lee features at TL and into the alpine. Field teams continue to monitor the sensitivity of these layers carefully, as should you!

Avalanche Summary

Natural avalanches up to size 1.5 were observed Tuesday in windswept alpine moraine features. Appears to be running on the persistent slab interface dow 30 to 50cm.

Confidence

Forecast snowfall amounts are uncertain on Thursday

Problems

Wind Slabs

Small inputs of fresh storm snow with southwesterly winds will continue to build layers of windslab in lee features at ridge crests and open areas at TL and above.

Be cautious as you transition into wind affected terrain.Be careful with wind loaded pockets while approaching and climbing ice routes.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

This problem is made up of 3 significant interfaces in the top 30-50cm of the snowpack. All interfaces seem to be slowly healing but have shown recent sensitivity to light loads in isolated locations.

Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Jan 25th, 2018 4:00PM