Avalanche Forecast

Issued: Feb 23rd, 2022 4:00PM

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

Catherine Brown,

Glacier.

Rider triggered avalanches are possible at moderate hazard. Test for reactivity of lingering wind slabs and a mid-February persistent weak layer.

Summary

Weather Forecast

Temperatures are gradually warming, bringing some clouds and isolated flurries, a storm is approaching on Saturday.

Tonight: Cloudy possible flurries, -19*C, light N winds

Thurs: Sun and cloud, Alp high -13*C, light NW winds

Fri: Mix of sun/cloud, Alp high -14*C, light SW winds

Sat: Mix of sun/cloud and flurries, Alp high -11*C, light SW winds

Snowpack Summary

Lingering and reactive windslabs from strong Nly winds exist at all elevations in open, exposed terrain. Cold temps are working to soften these slabs. The Feb 15 surface hoar/solar crust is down 50-80cm and most problematic at and below Treeline.

Avalanche Summary

We observed natural avalanches on Tuesday up to size 2.5. These were mostly wind slabs, with a couple solar triggered avalanches.

Numerous public reports this week of human triggered avalanches failing below surface wind slabs and on the Feb 15 SH/Crust layer. Size 2 partial burial on Avalanche Crest, Vaux Moraine, wind slabs on Cougar Creek East.

Confidence

The weather pattern is stable

Problems

Wind Slabs

Mod/strong SW winds during the weekend storm have flipped to mod/strong N'ly winds, thus distributing wind slabs on all aspects. Use caution at ridge crests, lee features, and open exposed, cross-loaded slopes at Treeline and above.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Watch for surface cracking and stiffer surface layers of snow.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Persistent Slabs

~60cm of snow and variable mod/strong winds have formed slabs, burying the Feb 15 persistent weak layer (surface hoar, 2-8mm, or a crust on steep solar aspects). The SH is more prevalent at Treeline and below, whereas the crust exists into the Alpine

Use caution on open slopes and convex rolls at treeline where buried surface hoar may be preserved.
Persistent slabs may be more sensitive to human triggering on solar asp where it sits on sun crust

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Feb 24th, 2022 4:00PM