Avalanche Forecast

Issued: Feb 25th, 2015 3:00PM

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

matt.mueller, Alberta Parks

Kananaskis.

We are approaching another flat line period in the forecast season. Its a good time to get out and do the longer classic tours with the longer days.

Summary

Confidence

Good

Weather Forecast

The temps will drop to -15 tonight with light winds at ridgetop. Tomorrow will see a mix of sun and cloud, no new snow and an alpine high of -7. The winds will be light at all elevations with variable directions. Even with the sun, we're expecting the freezing level to stay at valley bottom.

Avalanche Summary

No new observations today. Obscured skies for most of the day.

Snowpack Summary

Convective flurries and a mild upslope storm last night left variable amounts of new snow. On average the forecast region saw only 4cm's last night and another 3 throughout today. Not a huge change to the snowpack, but a slight refresh for sheltered areas. With the cooling temps, slabs in the alpine and upper treeline zones tightened up a bit. There are widespread windlabs in the alpine at the moment. For the most part these alpine slabs are well bonded, but in isolated areas(steep, immediate lee) there is a concern with a weaker midlayer within the slabs, down 20-30. Treeline also has windslabs, but these tend to be a bit softer and more focused to open areas. Sheltered areas have a light dusting with the new snow. Below treeline has seen little change except for the crusts freezing very well overnight.

Problems

Persistent Slabs

The cooler temps are helping to lock these slabs in place. We are becoming more comfortable with them, but still think there is a chance of setting them off in steep(40 degree +), crossloaded terrain.

Caution in lee and cross-loaded terrain near ridge crests.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Deep Persistent Slabs

The ground cover and elevation seem to be a factor here. This layer is much more prominent in high rocky terrain, where the depth hoar is more persistent and slow to change. Assess these transitional zones and watch for trends as you travel.

Be aware of thin areas that may propogate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

3 - 5

Valid until: Feb 26th, 2015 2:00PM