Avalanche Forecast North Columbia

Date Issued: Valid Until:

Avalanche Canada dsaly, Avalanche Canada

Avalanche Forecast

Sat Apr. 13th ยท 3:29PM

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low
Wind Slabs Wind Slabs

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Low

Below Treeline

Danger Ratings Low

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low
Flurries Saturday accumulated at upper elevations along with wind. Use caution around ridge crests and lee terrain features, where deposits will be most reactive and may also hide older, recently buried wind slabs.

Confidence

Moderate -

Weather Forecast

SATURDAY NIGHT: Cloudy with scattered flurries, up to 5 cm accumulation / southwest wind, 20-40 gusting to 55 km/h / alpine low -6 C / freezing level 800 mSUNDAY: Cloudy with sunny periods and isolated flurries, trace to 10 cm accumulation / west wind, 20-40 km/h / alpine high -2 C / freezing level 1600 mMONDAY: Mix of sun and cloud with isolated flurries / southwest wind, 10-15 km/h / alpine high -3 C / freezing level 1600 mTUESDAY: Cloudy with sunny breaks and isolated flurries / south wind, 15-30 km/h / alpine high -2 C / freezing level 1900 m

Avalanche Summary

On Thursday, a few human triggered loose wet avalanches up to size 1.5 were observed on steep slopes in the afternoon. Evidence of a solar-induced wet slab cycle on west aspect around 2400 m was reported on Friday.On Wednesday the avalanche activity decreased. A few natural and human triggered wind/storm slab avalanches up to size 2 were reported on west and north aspects at treeline and in the alpine.On Tuesday, several natural and human triggered storm/wind slab avalanches 20-40 cm deep and up to size 2.5 were observed on north and east aspects. Two of these were remotely triggered, one by humans and another one by a helicopter. A layer of small surface hoar below the most recent snow may have been the weak layer. Several natural wet slab and loose wet avalanches up to size 2.5 were reported from south and west aspects (see a MIN report from Glacier National Park).

Snowpack Summary

Up to 20 cm new snow covers a melt-freeze crust on all aspects except for north facing slopes above 2000 m, where the snow stayed dry. On north-facing aspects in the alpine, the recent 30-50 cm snow was redistributed by wind and, in isolated locations buried surface hoar. Older wind slabs sitting on surface hoar may still be sensitive to human triggers.Below treeline snow is disappearing rapidly.

Problems

Wind Slabs

Wind Slabs

Southwesterly winds have redistributed recent flurries and older storm snow, building slabs in wind loaded areas and covering older wind slabs. The most reactive deposits will be around ridge crests and in wind loaded terrain.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Watch for signs of instability such as whumpfing, or cracking. Wind slabs that are sitting on surface hoar may remain reactive to human triggers.

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Possible

Expected Size

1 - 2