Archived

Avalanche Forecast

Dec 14th, 2017–Dec 15th, 2017

Alpine

1: Low

The avalanche danger rating in the alpine will be low

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: South Coast Inland.

With snow and wind expected during the day on Friday watch for touchy wind slabs building in alpine, lee areas particularly in the Coquihalla area where forecasted precipitation amounts are highest.

Confidence

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

Weather Forecast

FRIDAY: Cloudy, flurries. Accumulation 5-15 cm (highest amounts in Coquihalla area). Ridge wind moderate from the west becoming northwest. Temperature -3. Freezing level 800 m.SATURDAY: Mix of sun and cloud, light flurries. Accumulation trace. Ridge wind light from the west. Temperature -5. Freezing level 700 m.SUNDAY: Cloudy, flurries. Accumulation 5-10 cm (highest amounts in Coquihalla area). Ridge wind moderate to strong from the west. Temperature -3. Freezing level 800 m.

Avalanche Summary

There have been no new avalanche reports since the weekend when numerous loose wet avalanches up to size 2 were observed on northerly aspects along the Duffey Lake Road with rapid daytime warming that occurred on Sunday.

Snowpack Summary

The recent alpine inversion and warm temperatures across the region have created a spring-like crust on most aspects. The exception is shaded north aspects at upper elevations where the snow surface consists of dry, sugary snow (facets). Beneath the snow surface the upper snowpack is well settled and overlies the late November rain crust, now 20-50 cm deep. Recent snowpack tests in the Duffey Lake area have produced hard, resistant compression test results on small sugary, snow crystals (facets) associated with this layer. However these facets were noted to be showing signs of "rounding" or gaining strength. Treeline snow depths are approximately 1 m throughout the region.

Avalanche Problems

Wind Slabs

The bond between the new snow and the old surface will be the big question once the storm snow starts to accumulate and be redistributed by winds.

Be careful in wind loaded areas, especially near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2