Avalanche Forecast

Issued: Apr 13th, 2018 3:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

New windslabs have/are developed in alpine terrain that skiers should pay close attention too. Choose supported features and rein yourself in a little. Watch for the affects of solar radiation on solar aspects later in the day.

Summary

Confidence

High -

Weather Forecast

Winds out of the SW are forecast to increase overnight further loading and building on the current windslabs. Conditions will be a mix of sun and cloud with daytime highs are -7C in the alpine. Pay attention to the sun, solar radiation is strong at this time of year and solar aspects will quikly become less stable as temperatures warm up. These decreases will be most apparent in thin, steep, rocky solar terrain.

Avalanche Summary

One size two wet slab was observed on the EEOR later in the day on Friday but otherwise, only isolated pinwheeling on solar aspects.

Snowpack Summary

SW winds increased in alpine overnight and into the morning building windslabs up to 20cm thick in lee features. Recent snow is overlying a supportive MFC that is 4-6cm thick up to 2200m. All aspects were moist up to 2000m by midday and moist snow suspected up to the peaks on solar. Hard sudden planar results on the March 15th crust down 50cm at 2200m on a SE aspect at treeline. Start early when travel on the crusts is good and fast

Problems

Wind Slabs

Windslabs up to 20cm thick in lee and crossloaded features. These slabs will build overnight on Friday and get a little bit larger and stiffer. Use Caution.

Avoid lee and cross-loaded terrain near ridge crests.Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

Lots of variability on this interface down 50cm. This is a persistent slab that is overlying a thick suncrust that was buried on solar aspects on March 15th.

Minimize exposure to sun exposed slopes when the solar radiation is strong.Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Cornices

Cornices are large and looming and become weak with daytime heating. They may collapse and trigger an avalanche on the underlying slopes.

Cornices become weak with daytime heating, so travel early on exposed slopes.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Apr 14th, 2018 2:00PM