Avalog Join
Archived

Avalanche Forecast

Dec 26th, 2024–Dec 27th, 2024
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
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
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate

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.

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.

Avalanche 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: Possible - Likely

Expected Size: 1 - 2.5

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: Possible - Likely

Expected Size: 1 - 1.5