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Avalanche Forecast

Jan 20th, 2025–Jan 21st, 2025
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
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: Glacier.

A persistent slab buried 30-50cm deep remains reactive in snowpack tests. A skier accidental (see avalanche summary) on Avalanche Mountain is further evidence that this problem is lingering.

Be prepared for the the cold with extra layers and know how to stay warm if your group has an unexpected hiccup.

Confidence

Moderate

Avalanche Summary

A persistent slab avalanche was reported by a third party in the Kors-Thomas bowl of Avalanche Mountain on Sunday. No details of the event are available but it appears to have been skier triggered.

Explosives testing on steep, northerly Treeline features on Saturday. Results up to size 1.5 were observed, with minimal propagation.

Snowpack Summary

~10cm of cold, faceted snow sits atop a denser, wind-pressed layer. Below this lies a weak interface (Jan 7th layer) down 30-50cm, comprised of surface hoar (all aspects) and/ or a thin crust on steep S aspects.

In the start zone of Mt Fidelity, moderate "resistant" and "sudden planar" snowpack test results were found down 30cm. We are keeping an eye on this persistent layer as the snowpack builds on top of it.

Overall the mid and lower snowpack is strong & well settled.

Weather Summary

More cold, clear, and calm.

Tonight Mainly cloudy. No precipitation: Nil. Alpine low -13 °C. Ridge wind SW 20 km/h.

Tues Cloudy with sunny periods and isolated flurries. Trace precipitation. Alpine high -12. Ridge wind W 25 km/h gusting 50.

Wed Sun and cloud. No Precipitation. Alpine high -8. Ridge wind W 15.

Thursday Mainly cloudy with isolated flurries. Trace precipitation. Alpine high -8. Wind SW 15 gusting 40.

Terrain and Travel Advice

  • Be especially cautious as you transition into wind-affected terrain.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks, or recent avalanches.

Avalanche Problems

Persistent Slabs

The Jan 7 persistent weak layer of surface hoar has been found in profiles both at treeline and in the alpine buried up to 60cm deep. Test results suggest that propagation is still possible on this layer. Expect more reactivity on southerly aspects where multiple crusts exist in the upper snowpack,

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1.5 - 2.5