Avalanche Forecast

Issued: Apr 14th, 2019 3:20PM

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

dsaly, Avalanche Canada

South Columbia.

New snow has accumulated at upper elevations along with westerly winds. Use caution around ridge crests and lee terrain features, where deposits will be most reactive.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain

Weather Forecast

SUNDAY NIGHT: Cloudy with clear periods and isolated flurries, trace to 5 cm snow / west wind, 10-20 km/h / alpine low -7 C / freezing level valley bottomMONDAY: Mix of sun and cloud with isolated flurries, trace to 5 cm / west wind, 10-15 km/h / alpine high 0 C / freezing level 1700 m TUESDAY: Cloudy with sunny periods and isolated flurries, 5 cm snow / southwest wind, 10-15 gusting to 45 km/h / alpine high +2 C / freezing level 1900 mWEDNESDAY: Cloudy with sunny periods and isolated flurries, trace to 5 cm snow accumulation / west wind, 20 gusting to 50 km/h / alpine low -7 C / freezing level 2100 m

Avalanche Summary

Late Saturday, storm snow was sluffing in steep terrain with skier traffic and gaining cohesion.On Friday morning, a size 2 storm slab was observed in a wind-loaded pocket on a west aspect in the alpine.On Wednesday, a skier triggered wind slab avalanche of size 1.5 on a north aspect at treeline was reported in the south of the region.On Tuesday, several natural and human triggered storm/wind slab avalanches 10-50 cm deep and up to size 2.5 were observed on north and east aspects in the alpine. A size 1.5 explosive triggered cornice did not trigger an avalanche on the northeast facing slope below. Several natural loose wet and wet slab avalanches up to size 2 were reported from southeast, south, west and northwest facing slopes (see a MIN report from Glacier National Park).

Snowpack Summary

5-20 cm snow accumulated above 1600 m on Sunday along with westerly winds. On most aspects this covers a melt-freeze crust; on north facing slopes in the alpine, new snow fell over the recent 20-50 cm wind-affected snow and, in isolated locations buried surface hoar. Older wind slabs sitting on surface hoar might still be sensitive to human triggers.Below treeline snow is disappearing rapidly.

Problems

Wind Slabs

New snow is being redistributed by wind. Fresh snow may hide older, recently formed wind slabs. Be cautious around ridge crest and lee terrain where depositions of new snow will be most reactive.

Be careful with wind-loaded pockets, especially near ridge crests and roll-overs.Be alert to conditions that change with elevation.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Loose Wet

Expect the snow surface to become moist and the likelihood of loose wet avalanches to increase on sun exposed slopes if the sun comes out.

Minimize overhead exposure to cornices above.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Use extra caution on slopes if the snow is moist or wet.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 15th, 2019 2:00PM