Avalanche Forecast

Issued: Mar 22nd, 2017 4:31PM

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

mbender, Avalanche Canada

Kootenay Boundary.

The avalanche danger will gradually increase through the end of the week into the weekend as forecast precipitation amounts begin to accumulate

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Friday

Weather Forecast

THURSDAY: Mix of sun and cloud / Light south wind / Alpine temperature -4 / Freezing level 1300mFRIDAY: Flurries, accumulation 5-10cm / Moderate southwest wind / Alpine temperature -3 / Freezing level 1300mSATURDAY: Flurries, accumulation 5-10cm / Moderate southwest wind / Alpine temperature -4 / Freezing level 1400m

Avalanche Summary

Reports from Tuesday indicate snowballing and loose snow avalanches to size 1 from steep terrain on all aspects from tree line and below.

Snowpack Summary

Last weekend rain soaked the upper snowpack for a second time in a week all the way to mountain tops. Subsequent cooling temperatures then formed a 10-30cm rain crust. In many parts of the region above the 1500m there may now be 10-15cm of new snow sitting on top of the crust. Below the crust expect to see moist or wet snow. The late-February facet / surface hoar interface (70-120 cm deep), the mid-February crust (90-130 cm deep), and basal facets in shallow snowpack areas may still be present at upper elevations and may still be reactive and become a concern as surface crusts break down with daytime warming.

Problems

Loose Wet

As the freezing level rises and/or the sun comes out the surface snow will become increasingly wet or moist and may begin to sluff from steep terrain.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.If triggered smaller avalanches may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

At upper elevations where the recent rain crust is not as thick and strong, there is still potential to trigger deeper buried weak layers.

Be alert to conditions that change with elevation.Be aware of thin areas that may propogate to deeper instabilites.Pay attention to overhead hazards like cornices which could easily trigger deep slabs.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Mar 23rd, 2017 2:00PM