Avalanche Forecast

Issued: Jan 31st, 2023 4:00PM

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

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Watch for unstable wind slabs in alpine terrain. Recent northerly wind has left slabs in atypical areas.

Summary

Confidence

High

Avalanche Summary

No new avalanches were reported over the weekend, although whumpfing on stiff wind slabs was reported at upper treeline and alpine elevations.

Snowpack Summary

Northerly outflow winds have affected open areas in the alpine and treeline, scouring windward slopes and redistributing this storm snow into pockets of stiff wind slabs in lee areas. A crust exists on the surface at lower elevations and on steep solar aspects to 1800 m. Softer snow still exists in sheltered areas at treeline and below.

Generally, the middle and lower snowpack is strong and bonded. Isolated weak layers may exist within the middle and lower snowpack, but the thick crusts sitting above them make triggering avalanches on these layers unlikely.

Snowpack depths are 150 to 200 cm at treeline and taper rapidly below 1500 m.

Weather Summary

Tuesday night

Overnight flurries with up to 5 cm of snow, 30 to 40 km/h southwest wind, treeline temperatures around -6 ˚C.

Wednesday

Mostly cloudy, isolated flurries with trace amounts of snow, 30 to 40 km/h southwest wind, treeline temperatures warm to -3 ˚C.

Thursday

Mix of sun and cloud, no precipitation, 30 to 50 km/h southwest wind, freezing level climbs to 1200 m with treeline temperatures warming to -3 ˚C.

Friday

Cloudy with scattered flurries bringing 1 to 5 cm of new snow, 40 to 60 km/h south wind, freezing level around 1500 m with treeline temperatures around -2 ˚C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
  • Use ridges or ribs to avoid areas of wind loaded snow.
  • Wind slabs may be poorly bonded to the underlying crust.

Problems

Wind Slabs

An icon showing Wind Slabs

Northerly outflow winds have redistributed snow into stiff wind slabs in lee south aspect terrain. Wind slabs may be reactive to human triggering where they overlie a slick crust. Seek out sheltered terrain where you can avoid wind slabs and find good riding.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 1st, 2023 4:00PM