Avalanche Forecast
Issued: Dec 26th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Loose Wet.
Avalanche Canada,
Avalanche Canada
Tune into the reactivity of wind redistributed and/or sun-exposed snow and pull back to low-consequence terrain if you encounter signs of instability.
Summary
Confidence
Moderate
Avalanche Summary
A size 2 storm slab was triggered accidentally by a skier walking along a ridgeline in the Mount Washington area on Wednesday. It occurred on a northwest-facing 30-degree slope at treeline, fractured 100 m wide, ran 50 m, and featured a 40 cm crown. Numerous size 1 - 1.5 slabs were observed throughout north-facing terrain in the same area. An island-wide large natural avalanche cycle likely proceeded through the overnight period.
Snowpack Summary
The Christmas storm brought 40 - 60 cm of new snow to the Island's remote weather stations. Accumulations in the west coast alpine are likely significantly higher. Wind-affected areas have a wide-ranging 0 - 200 cm sitting on the pre-storm crust!
Fluctuating freezing levels formed at least two mid-storm failure planes in the new snow, both of which continued to produce moderate, sudden snowpack test results on Thursday. These weaknesses are expected to stabilize relatively quickly.
Below the new snow, the snowpack is thoroughly settled and bonded.
Snowpack depths at treeline are now about 130 -180 cm on the north and south island, closer to 250 to 300 cm on the central island.
Weather Summary
Thursday night
Cloudy with scattered flurries bringing up to 5 cm of new snow. 20 to 30 km/h southwest ridgetop wind shifting southeast and easing. Freezing level 1100 m.
Friday
Mainly cloudy with isolated flurries, increasing overnight. 10 to 40 km/h southeast ridgetop wind, increasing. Freezing level 1200 m.
Saturday
Cloudy with continuing wet flurries bringing 15 to 30 cm of new snow, including overnight amounts. 50 to 60 km/h southwest ridgetop wind. Freezing level 1400 m.
Sunday
Cloudy with scattered flurries bringing up to 5 cm of new snow. 30 to 40 km/h southeast ridgetop wind. Freezing level 1000 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be especially cautious as you transition into wind-affected terrain.
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Even brief periods of direct sun could produce natural avalanches.
Problems
Wind Slabs
Steep, wind loaded features remain suspect in the wake of the storm.
Aspects: North, North East, East, West, North West.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Brief periods of sun could cause new snow to become unstable on sun-exposed aspects. Loose wet avalanches may be triggered naturally or with rider traffic.
Aspects: South East, South, South West.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 27th, 2024 4:00PM
