Avalanche Canada cgarritty, Avalanche Canada

Northwest Coastal Avalanche Forecast

Jan 12th, 2020 4:00PM

Be on alert for newly formed wind slabs if you're braving the cold on Monday.

Summary

Confidence

High -

Weather Forecast

Sunday night: Clear. Moderate to strong northeast winds, decreasing.

Monday: Sunny. Light to moderate northeast winds. Alpine temperatures around -24.

Tuesday: Sunny. Light to moderate east or northeast winds. Alpine temperatures around -24.

Wednesday: Sunny. Light to moderate east or northeast winds, increasing over the day. Alpine temperatures around -27.

Avalanche Summary

Reports from Saturday included more extensive observations of Friday's avalanche cycle. These observations varied over the region from more extensive natural activity to size 2 (large) at all elevations in areas west of Terrace to more limited activity to the east, likely owing to variable new snow accumulation. Observations of newer activity were generally reduced, including a mix of dry loose, smaller wind slabs, and one large (size 2) storm slab triggered with a ski cut.

Looking forward, wind redistributed surface snow will remain our primary concern. Under forecast cool temperatures, sheltered snow may continue to react to human triggers as dry loose sluffs. Greater danger should be expected in exposed areas where winds have created deeper and more reactive slabs. 

Snowpack Summary

30-50 cm of new snow accumulated over the region on Friday. In many areas this recent snow is expected to be heavily wind-affected by recent outflow winds. It mainly buried wind-affected surfaces at alpine and upper treeline elevations, but may cover a new layer of surface hoar at lower elevations and in sheltered areas or a thin sun crust on steeper south-facing slopes.

Below the new snow interface, 80-100 cm of older storm snow, also wind affected, has been forming a good bond with an underlying crust found up to about 1400 metres.

Below these layers the snowpack is generally well consolidated. Two older layers of surface hoar are now buried 130-180 cm deep. The recent storm cycle was a good test of these layers, with no reports of avalanches stepping down to them.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.
  • Avoid freshly wind loaded terrain features.

Valid until: Jan 13th, 2020 5:00PM