Avalanche Forecast

Issued: Jan 25th, 2023 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is below threshold. Known problems include Wind Slabs and Loose Wet.

Avalanche Canada jpercival, Avalanche Canada

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Strong winds and new snow available for wind transport maintain the current avalanche danger rating and will continue to build upon already reactive wind slabs.

Adopt a conservative terrain travel strategy that avoids steep north aspect terrain and seeks out low-angle well supported terrain.

Expected warming and potential sun effect will encourage the surface snow to become unconsolidated, especially on steep south-aspect treeline terrain.

Summary

Confidence

Moderate

Avalanche Summary

Tuesday: No new avalanches were reported or observed.

Monday: The south klondike highway operation reports a naturally occurring large (size 2) avalanche cycle on E through to Ne aspects in the alpine.

Sunday, A mountain information network report outlines both conditions and the observation of a naturally occurring small (size 1) avalanche. This avalanche appears to have failed near the ground and was reported to have occurred on a northeast aspect in the Fraser lakes area. See embedded MIN for pictures and review.

Saturday reports provided by the Skagway white pass avalanche control program, indicate that utilizing explosives 26kg or greater initiated numerous large avalanches (size 2 to 2.5).

Snowpack Summary

A strong southerly wind has and will continue to transport available new snow that has cross-loaded and created wind slabs at depths reported between 60 to 70 cm.

These new accumulations overlie an upper snowpack consisting of 15 to 30 cm of both new storm snow and unconsolidated faceted snow. The midpack presents as very dense with a reactive mid-December layer buried down between 40 to 55 cm.

Snowpack depths vary due to wind transport with averages at treeline reported as 125 cm and 200 cm in the alpine. In areas where the snowpack is less than 1 meter in depth, it is reported to be quite faceted and unconsolidated.

Weather Summary

Wednesday night

Cloudy with light snowfall, 5 to 10 cm of accumulation. Alpine temperatures are 0 °C. Southwest ridge wind 100 km/h easing to 60 km/h. Freezing level is 1500 m descending to 1100 m.

Thursday

Cloudy with no new precipitation. Alpine temperatures 0 °C cooling to -4 °C. Ridge wind Southwest 50 km/h. Freezing level is 1100 m descending to 500 m.

Friday

Clearing with no new precipitation. Alpine temperatures -8 °C. Ridge wind northwest 60 km/h. Freezing level 0 m.

Saturday

Clearing with no new precipitation. Alpine temperatures -20°C. Ridge wind northeast 10 km/h. Freezing level 0 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.
  • Pay attention to the wind, once it starts to blow fresh sensitive wind slabs are likely to form.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.

Problems

Wind Slabs

An icon showing Wind Slabs

Past and continued strong southwesterly winds have encouraged rapid wind slab formation in lee areas. Assess for changing conditions throughout the day and as you gain elevation or change aspects.

Use extra caution in leeward terrain features.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

Most likely to occur on steep south-aspect terrain.

Expect even wet loose avalanches to have the potential to push a rider into or over terrain traps such as cliffs and gulley features.

Aspects: All aspects.

Elevations: Below Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 26th, 2023 4:00PM