Avalanche Canada cgarritty, Avalanche Canada

South Rockies Avalanche Forecast

Nov 23rd, 2018 5:07PM

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

Limited field observations mean that this forecast should be used as your initial assessment before gathering additional information in the field.

Summary

Confidence

Low - Due to the number of field observations

Weather Forecast

Friday night: Cloudy with clear periods. No new snow.Saturday: A mix of sun and cloud. Light northwest winds. Alpine high temperatures around -7.Sunday: Mainly sunny. Light to moderate southwest winds. Alpine high temperatures around -4.Monday: A mix of sun and cloud. Strong southwest winds. Alpine high temperatures increasing to around 0 as freezing levels rise to 2500 metres.

Avalanche Summary

No new avalanches have been reported in the region. A Mountain Information Network post from Monday details a large (size 2) skier-triggered wind slab in a steeper wind-loaded feature in the alpine in the Mause Creek area in the west of the region. The slab had a depth of 25-40 cm and featured a 50 m wide crown fracture line.

Snowpack Summary

Light snowfall over Thursday buried a widespread layer of weak, feathery surface hoar crystals with about 5-10 cm of new snow. Below the surface hoar, the new snow has also buried pockets of recently reactive wind slab in wind-exposed terrain at treeline and above. This wind-affected layer sits above a complex of late-October and early-November melt-freeze crusts and facets found at the base of the snowpack at treeline and above. Snowpack depths taper quickly as elevation decreases and snow depths below treeline generally remain below threshold depth for avalanching.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible

Expected Size

1 - 1.5
Light new snow is likely to have formed thin new wind slabs in the lee of exposed features at high elevations. The new snow may also be obscuring older, more stubborn wind slab.
Increase your caution as you transition into wind affected terrain.Examine slopes for patterns of wind transport and avoid steep patches of stiff, slabby snow.

Aspects:

All aspects.

Elevations:

Alpine.

Valid until: Nov 24th, 2018 5:07PM