Avalanche Forecast
Issued: Dec 22nd, 2021 4:23PM
The alpine rating is Wind Slabs and Loose Dry.
, the treeline rating is , and the below treeline rating is Known problems includeLisa Paulson,
Wind slab development continues with strong winds and new snow forecasted. On Christmas Eve we slide into a period of dangerously cold temperatures for the foreseeable future....
Summary
Weather Forecast
Moderate to strong SW winds are forecasted to continue as a low pressure system pulls away from the region delivering 5-15 cm overnight, and possibly another 10 on Thursday as a cold front passes mid-day tomorrow. Behind the cold front, temperatures will drop and winds will ease. Fri-Sat cold arctic air becomes entrenched (highs in the minus 20's)
Snowpack Summary
Strong winds with up to 20 cm tonight and Thurs will contribute to the windslab problem. There is 50-90 cm over the Dec 2 rain crust which exists below 2200 but is not yet active but we are watching this layer very closely and expect it may develop into a problem soon.
Avalanche Summary
Both SSV and LL ski area report thin windslab formation from strong winds Tues & Wed, up to size 1.5. Also noted a ~3 day old unusual size 2 avalanche at 2000m on Tumbling Peak in Kootenay Park in a very shallow snowpack area. Looked like someone may have taken a nasty ride.
Confidence
Problems
Wind Slabs
New snow and strong winds will create new windslabs that may bond poorly to the old surface. Manage your terrain choices carefully on Thursday to avoid leeward areas.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Dry
Expect this problem to emerge in areas that receive more snow (~20 cm). There is uncertainty in the weather models where predicted amounts range from 5-25 in the next 24 hrs.
- Be careful of loose dry power sluffing in steep, confined or exposed terrain.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 23rd, 2021 4:00PM