Avalanche Forecast

Issued: Jan 10th, 2024 4:00PM

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

Avalanche Canada zryan, Avalanche Canada

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Northerly winds are expected to form wind slabs in atypical areas and at lower elevations than you might expect.

Summary

Confidence

Moderate

Avalanche Summary

On Tuesday near Mount Washington, several skier-triggered storm slabs up to size 1.5 were reported from steep or wind-loaded terrain at treeline. One size 1.5 natural storm slab was observed on a north aspect at treeline.

Looking forward to Thursday, winds will shift around to the northwest as arctic air invades the region. Fresh, reactive wind slabs may form in a reverse-loading pattern and at lower elevations than is typical.

Snowpack Summary

40 to 90 cm of recent storm snow will continue to be redistributed by strong northwesterly winds throughout the day. In windward areas, expect the surface to be stripped back to ground or a crust that exists up to 1400 m.

The remainder of the snowpack is strong, with numerous hard melt-freeze crusts.

Treeline snow depths generally range from 50 to 150 cm. Snow depth diminishes rapidly below 500 m where there has been more rainfall.

Weather Summary

Wednesday Night

Mainly clear with cloudy periods and no new snow. Northwesterly winds 40 to 90 km/h. Treeline temperatures drop to -8 C.

Thursday

Sunny with cloudy periods and no new snow. Northwesterly winds 50 to 100 km/h. Treeline temperatures drop to -12 C.

Friday

Mainly sunny with no new snow. Northwesterly winds 30 to 80 km/h. Treeline temperatures drop to -16 C.

Saturday

Sunny with no new snow. Northwesterly winds 20 to 50 km/h. Treeline temperatures around -15 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
  • Keep your guard up at lower elevations. Wind slab formation has been extensive.

Problems

Wind Slabs

An icon showing Wind Slabs

Winds have shifted to the northwest, and may be forming fresh, reactive slabs in a reverse-loading pattern and at lower elevations than is typical.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Jan 11th, 2024 4:00PM