Avalanche Forecast

Issued: Dec 5th, 2017 4:31PM

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

Avalanche Canada shorton, Avalanche Canada

Intense warming is on the way and it's tricky to predict how it will impact the snow. Make conservative terrain choices and avoid sun exposed slopes.

Summary

Confidence

Moderate - Freezing levels are uncertain on Wednesday

Weather Forecast

WEDNESDAY: Sunny with valley cloud in the morning, light northwest wind, inversion forming with alpine temperatures reaching -2 C.THURSDAY: Sunny with valley cloud, light wind, inversion with freezing level up to 3000 m.FRIDAY: Sunny with valley cloud, light wind, inversion with freezing level up to 2700 m.

Avalanche Summary

On Tuesday, explosive avalanche control in the Monashees produced a few size 1.5 slabs running on the November crust on northwest-facing slopes at treeline. A large size 3 natural avalanche was reported on a steep north-facing alpine face in the Selkirks. The failure layer is unknown, but it was likely an early season crust. Some sluffing from steep sun-exposed slopes was also reported.

Snowpack Summary

The snowpack is about to experience a big change with a week of warm sunny weather ahead. Intense warming is expected on steep south-facing slopes, while dry snow may persist on north-facing slopes. Snow from last week's storms has been redistributed into fresh wind slabs by northwest winds. Roughly 40-80 cm of recent snow sits above crusts from the warm weather in late November. Most reports suggest the snow is bonding to the crusts so far, but there's potential for this layer to become reactive with the intense warming. Snow depths decrease rapidly below treeline, where the primary hazards are rocks, stumps, and open creeks.

Problems

Storm Slabs

An icon showing Storm Slabs
Storm slabs will become touchy as the snow warms up, especially on steep south-facing slopes. Also watch for wind-loaded slopes around ridges and gullies.
Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Choose well supported terrain without convexities.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 6th, 2017 2:00PM