Avalanche Forecast

Issued: Feb 16th, 2014 8:15AM

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

triley, Avalanche Canada

Kootenay Boundary.

Incremental loading is expected to reach the tipping point as forecast new snow and wind add to the load of storm snow.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

Overnight and Monday: 10-15 cm of snow above 1000 metres overnight with strong Southwest winds. Another 10-15 cm during the day combined with moderate Southwest winds and freezing levels rising to about 1500 metres.Tuesday: Snow ending overnight and a chance of broken skies during the day. Light Southwest winds building during the day to strong by evening as the next pulse of moisture moves quickly into the region.Wednesday: Snow ending by early morning. Winds becoming light Southwest with high cloud and some sunny breaks.

Avalanche Summary

Explosive control produced many size 2.0 avalanches in the storm snow. Forecast new snow and very strong winds are expected to add to the load above the buried weak layers. Human triggering is expected to continue, and natural avalanches may result from the new storm loading.

Snowpack Summary

40-50 cm of recent storm snow has been transported into deep pockets of wind slab on North thru East aspects. Below the storm snow there is about 20 cm of snow from last week that buried the late January layer of crusts and/or facets and surface hoar. This persistent weak layer from Late January continues to be the sliding layer for natural and human triggered avalanches. The mid snowpack is well settled and strong. The deeply buried weak layers of early season facets and depth hoar have been dormant, but they may become reactive with the right combination of added load and warm temperatures. The forecast new snow and wind are expected to add to the load above the late January weak layer, and may result in avalanches running naturally or increased sensitivity to human triggers at this interface.

Problems

Storm Slabs

Forecast new snow and strong winds are expected to add yet another incremental load to the snowpack. Weak layers within the storm snow may be found from temperature changes and/or wind events. Long propagations and remote triggering may be likely.

The new snow will requires several days to settle and stabilize.>Avoid avalanche terrain during periods of heavy loading from new snow and wind.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 4

Persistent Slabs

There are several buried crusts and or surface hoar layers that developed in the end of January and during the cold weather earlier this month. Avalanches releasing on these layers may be large with serious consequences.

Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Avoid areas with overhead hazard.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

3 - 5

Valid until: Feb 17th, 2014 2:00PM