Avalanche Forecast

Issued: Feb 19th, 2014 8:47AM

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

triley, Avalanche Canada

Kootenay Boundary.

Widespread natural avalanche cycle continues. See blogs for more info.

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Thursday

Weather Forecast

Overnight and Thursday: Strong Southwest winds and another 10 cm of snow starting early in the morning. There may be a brief break in the late morning, and then another 10 cm of snow starting in the afternoon with moderate Westerly winds. Freezing level below 1000 metres.Friday: Snow ending early morning as the winds shift to moderate Northwest. Freezing level at valley bottoms.Saturday: Clear overnight becoming mostly cloudy by the afternoon. Alpine temperatures around -15

Avalanche Summary

Widespread natural slab avalanche activity up to size 3.0 on all aspects and elevations. Remote triggering and long fracture propagations continue. Endless settlements and whumphing experienced while traveling on low angle terrain. Low elevation cut-blocks are releasing naturally at the February 10th interface.

Snowpack Summary

There is over a metre of recent storm snow that is sitting on a weak layer that is a mixture of facets, surface hoar, and melt-freeze crusts. The weak layer is widespread at all elevations and aspects. The storm slab continues to settle and become more cohesive allowing for longer fracture propagations and remote triggering. This persistent weak layer is expected to be a concern for some time; at least through the weekend.

Problems

Storm Slabs

The natural avalanche cycle is expected to continue with another load of new snow and wind added to the storm slab.

Avoid avalanche terrain during periods of heavy loading from new snow and wind.>The new snow will requires several days to settle and stabilize.>Extra caution needed around cornices with current conditions.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 5

Persistent Slabs

Expect the deeply buried weak layer to continue to produce very large and destructive avalanches. Each load of new snow adds to the storm slab above the weak layer.

Avoid areas with overhead hazard.>Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Avoid runouts where triggering slopes from below is possible.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

3 - 6

Valid until: Feb 20th, 2014 2:00PM