Avalanche Forecast

Issued: Jan 15th, 2017 4:47PM

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

Avalanche Canada mgrist, Avalanche Canada

Wind slabs can currently be found on almost any aspect. Expect those on steep southerly slopes to be especially touchy.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

Big change is coming with significant snow (and some rain) through to Thursday. MONDAY: Mix of rain and snow (10-20 cm at higher elevations) beginning near noon. Winds strong from the southwest. Freezing level 1400m and alpine high temperatures to 0 Celsius. TUESDAY: Mix of rain and snow (up to 35cm at higher elevations). Winds moderate to strong (35-70 Km/hr) from the south. Freezing level 2000 metres with alpine temperatures to +1 Celsius. WEDNESDAY: Snow (15-25cm) throughout the day. Winds moderate to strong (35-70 Km/hr) from the south. Freezing level 1600m and alpine temperatures around 0 Celsius.

Avalanche Summary

Several skier (accidental) triggered Size 1 wind slabs were reported on S to SE aspects above 2000m on Saturday.

Snowpack Summary

We have wildly variable surface conditions due to wind and sun effect. The pleasant warm weather this weekend resulted in a sun crust on steep solar (south) aspects. Last week, strong winds 'reverse loaded' snow in the alpine and also affected treeline elevations too. Touchy wind slabs (5-40 cm thick) formed on southerly slopes near ridge crests and roll-overs. These slabs are the primary weakness of concern in the snowpack, giving easy sudden planar results in snowpack tests. Deeper in the snowpack, older snow is bonding fairly well to a variable surface consisting of a mix of soft wind slabs, hard wind slabs, sastrugi, faceted snow, and even some surface hoar. Snowpack layers below this interface are generally well bonded, and the lower snowpack is solid.

Problems

Wind Slabs

An icon showing Wind Slabs
Watch for soft slabs on sheltered northerly aspects, and touchy wind slabs on 'reverse loaded' southerly aspects. Expect the stability of slabs to deteriorate with loading from new snow/rain.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Use caution in lee areas. Recent wind loading has created wind slabs.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Jan 16th, 2017 2:00PM