Avalanche Forecast

Issued: Apr 6th, 2017 3:24PM

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

shorton, Avalanche Canada

Northwest Inland.

Most slabs avalanches in the past week have been triggered by cornices. Be cautious in wind affected terrain.

Summary

Confidence

Moderate - Due to the number and quality of field observations

Weather Forecast

FRIDAY: Cloudy with isolated flurries, strong southeast wind, freezing level up to 1500 m after an overnight freeze.SATURDAY: 5-10 cm of new snow, light southeast wind, freezing level around 1400 m.SUNDAY: Mostly cloudy, moderate south wind, freezing level around 1300 m.

Avalanche Summary

Several thin wind slabs were reported in northerly terrain in the Howsons on Wednesday. A few cornice triggered slabs have been reported throughout the region over the past week (up to size 2.5).

Snowpack Summary

Strong winds with light amounts of snow formed fresh wind slabs in exposed terrain on Wednesday. Elevations below about 1300 m are experiencing a daily melt-freeze cycle. Hard crusts form overnight and become moist during the heat of the day. Hard crusts may be found at higher elevations, particularly on slopes that were sun-exposed. The February crust and facet layer is 70-90 cm deep in the Houston Telkwas sled area and a deep persistent faceted weak layer is still lingering near the bottom of the snowpack in all areas.

Problems

Cornices

Cornices have been growing and may fall off naturally with daytime warming.

Cornices become weak with daytime heating, so travel early on exposed slopes.Minimize exposure to overhead hazard from cornices.Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 2

Wind Slabs

Strong winds and light amounts of snow have likely left wind slabs in the lee of exposed terrain.

Use extra caution on slopes if the snow is moist or wet.Use ridges or ribs to avoid pockets of wind loaded snow.Be alert to conditions that change with elevation.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 7th, 2017 2:00PM