Avalanche Forecast

Issued: Dec 15th, 2017 3:57PM

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

jmcbride, Avalanche Canada

South Coast.

Winter is set to return with a storm system expected to arrive late Saturday and into Sunday. The storm snow may be easily triggered, especially in "fat" areas that have seen additional loading from wind.

Summary

Confidence

Moderate - Freezing levels are uncertain on Sunday

Weather Forecast

SATURDAY: Flurries. Accumulation 5 cm. Ridge wind light from the west. Temperature near 0. Freezing level 800 m.SUNDAY: Snow. Accumulation 15-20 cm. Ridge wind moderate from the southwest. Temperature near 0. Freezing level 1200 m.MONDAY: Flurries. Accumulation 5-10 cm. Ridge wind light from the west. Temperature near 0. Freezing level 800 m.-

Avalanche Summary

No new avalanches have been observed during the past week however, some rather large blocks of snow were observed to topple over from the base of a steep, rocky outcrop depositing a 10 m wide debris pile across a snowshoe trail on Monday.

Snowpack Summary

Beneath the new storm snow lies a widespread melt-freeze crust on all aspects and elevations. On north aspects the crust is likely quite hard while on southerly aspects and at lower elevations the crust may still be moist. Below the snow surface, the upper snowpack is well-settled an sits on the late-November rain crust. This crust is now buried approximately 120 cm at 1300m elevation, and is up to 30 cm thick. Beneath the November crust, the lower snowpack is wet to ground. Below treeline the snow pack is thin and there are many early season hazards. Snowpack depths range from 30 cm at 800 m elevation to 180 cm at 1220 m.

Problems

Wind Slabs

New snow and wind will build slabs in leeward, wind-loaded areas. These may be easy to trigger in areas where they overly a hard crust rather than moist snow.

Be careful with wind loaded pockets in leeward areas especially near ridge crest and roll-overs.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

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