Avalanche Forecast

Issued: Feb 21st, 2014 7:15AM

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

matt.mueller, Alberta Parks

Kananaskis.

The new snow load is the question right now. Given the touchy snowpack, even a light load will tip the scales and cause a natural cycle. It would be fair to place treeline at the upper end of Considerable right now. Not the time to push terrain.

Summary

Confidence

Good

Weather Forecast

A bit more snow will accompany the cold front passing through over night. In all we can expect 10cm's by tomorrow. The good news is that this snow is coming in with almost no wind, even in the alpine. Tomorrow's temps will hover around -14 at valley bottom. Trace amounts through the week-end. Light winds throughout the week-end as well.

Avalanche Summary

Today we came across 3 large avalanches that are thought to be from the last 24hrs. The debris was fresh despite the new snow. All 3 avalanches came out of terrain that had previously avalanched. South side of Hero's knob, SE-S asp, alpine start zones, sz2.5.

Snowpack Summary

Steady snow today on the Spray has currently left 4cm's (as of 3pm) with another 6 expected overnight. So far this new appears to be bonding well to the snow from last week. The snow from last week has either settled or been wind distributed to form a cohesive slab. The density of this slab increase with altitude and exposure to wind. The common theme at all elevations/aspects is the extremely poor bond with the snow underneath. Today marks the 7th day since the burial of the facets and there has been no improvement with the bond. On all of our field trips this week we have experienced LOTS of whumphing, cracking and even remote avalanches. The weak layer is made up of facets and in the odd place broken down surface hoar. One of the weaker snowpacks in recent memory. Snow depths are: Burstall Pass-165, Burstall Parking-118.

Problems

Persistent Slabs

The layers above the Feb 11th layer are gaining strength which has a negative impact on avalanche conditions. Propagations will get larger as the slab density increases. Whumphing and cracking continue at all elevations.

Avoid open slopes with any steepness over 30 degrees.>Be careful with low angle slopes that may not normally be a concern.>Avoid areas with overhead hazard.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 4

Wind Slabs

There are pockets of windslabs evident from last week's wind event. They are expected to be found at open tree line areas and lower alpine.

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

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Feb 22nd, 2014 2:00PM