Archived

Avalanche Forecast

Dec 17th, 2017–Dec 18th, 2017

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: South Coast Inland.

Wind slabs may be found in immediate lee (down wind) features at higher elevations. Watch for how the new snow is bonding to the old surface on south aspects.

Confidence

Moderate - Due to the number of field observations

Weather Forecast

Monday will see a brief lull in the active weather pattern before significant precipitation arrives on Tuesday.MONDAY: Cloudy with isolated flurries. Accumulation of 5 cm possible. Ridge wind moderate from the west. Temperature near -5. Freezing level 700 m.TUESDAY: Snow. Accumulation 15-25 cm. Ridge wind moderate from the southeast. Temperature near -7. Freezing level 500 m. WEDNESDAY: Clearing in the morning. Ridge wind moderate northerly. Freezing level at the surface.

Avalanche Summary

Small natural dry loose avalanches to Size 1 were reported in the north of the region (Duffey Lake zone) on Saturday.

Snowpack Summary

10-20cm of new snow covers crusts of variable thickness that formed on almost all aspects in early December. On steep southerly aspects the crust is supportive, whereas on northerly aspects the crust is quite thin and variable. In the south of the region (Coquihalla), moderate southerly winds have redistributed the storm snow, creating wind slabs on northerly aspects behind ridge crests and rib features. Lower down, the snowpack is well settled and overlies the late November rain crust, now 20-50 cm deep. Treeline snow depths are approximately 1 m throughout the region.

Avalanche Problems

Wind Slabs

Stubborn wind slabs have formed in immediate down wind (lee) features at ridge top elevations.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2