Avalanche Forecast

Issued: Apr 2nd, 2015 9:15AM

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

jlammers, Avalanche Canada

South Rockies.

Warmth remains the primary driver of avalanche hazard as we shift into a more spring like pattern. Minimize your exposure to large slopes if the snowpack is becoming moist or wet.

Summary

Confidence

Fair - Due to the number of field observations

Weather Forecast

Expect a mix of sun and cloud on Friday. On Saturday, a pacific front will move inland although only trace amounts of new snow are expected. By Sunday, a short-lived ridge should bring mainly clear skies. Ridgetop winds should be light from the southwest, becoming moderate with Saturday's pulse. Daytime freezing levels should hover around 1500m.

Avalanche Summary

We have had no recent reports of avalanche activity.

Snowpack Summary

Observations have been extremely limited, although I expect light amounts of low-density snow overlie a widespread and supportive melt-freeze crust,. Gusty winds may have redistributed the surface snow resulting in wind slab formation in the alpine. The mid-March rain crust is down 35 to 70cm and has shown a good bond with snow above. Old persistent weak layers are still intact in the mid and lower snowpack and there may be potential for these layers to wake up with a big cornice fall, sustained warming and/or a significant rain event.

Problems

Wind Slabs

Gusty ridge top winds have been observed, and loose surface snow has likely been redistributed into small wind slabs in high elevation terrain.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.>Travel on ridgetops to avoid wind slabs on slopes below, but be careful with cornices!>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Cornices

Large cornices hang precariously over many ridge-lines. While cornice failure is problematic enough on its own, don't discount the ability for falling cornices to release bigger slab avalanches.

Give cornices a wide berth when traveling on or below ridges. Remember that cornices become weak with daytime heating.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Apr 3rd, 2015 2:00PM