Avalanche Forecast

Issued: Dec 25th, 2017 3:55PM

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

jmcbride, Avalanche Canada

South Coast.

It may have been a white Christmas, but don't expect much change until we ho, ho, hopefully see some appreciable precipitation later in the week.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Thursday

Weather Forecast

TUESDAY: Mix of sun and cloud. Ridge wind light from the west. Temperature -4. Freezing level surface.WEDNESDAY: Mostly cloudy, flurries. Accumulation 5 cm. Ridge wind light to moderate from the southwest. Temperature -3. Freezing level surface.THURSDAY: Snow. Accumulation 15- 25 cm. Ridge wind moderate from the southwest. Temperature +1. Freezing level 1000 m.

Avalanche Summary

There have been no new reports of avalanche activity since last Wednesday when a natural Size 2 slab avalanche was reported on a southeast aspect at 1400 m on the North Shore mountains, as well as a Size 1 on a west aspect at 1200 m.

Snowpack Summary

A light dusting of new snow now covers the variable old surface consisting of; wind-scoured northwesterly slopes, areas of hard and soft wind slab on alpine lee slopes and exposed treeline areas, as well as a thin sun crust on steep solar aspects. Approximately 2-5 cm of new snow overlies 15-30 cm of old storm snow on top of the most recent December 18th melt-freeze crust, which has been unreactive in recent snowpack tests. Below this crusts lies 20 cm of well settled snow above the December 16th crust. Below this crust, a third crust, the 20 cm thick late-November crust, is now buried 40-50 cm. The lower snowpack well settled and moist to ground. Snowpack depths are about 135 cm at 1100 m elevation, with many early season hazards present at lower elevations.

Problems

Wind Slabs

Recent variable winds have formed pockets of wind slab on most aspects in the alpine and exposed areas at treeline. These slabs overlie the December 18th crust and may still be sensitive to human triggering.

Be cautious as you transition into wind affected terrain.Watch for areas of stiff or hollow feeling snow, whumpfing, or shooting cracks.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Dec 26th, 2017 2:00PM