Avalanche Forecast
Regions: Glacier.
A reactive storm slab is present throughout the park. This is sitting on a weak base of sugary crystals.
There may be some significant settlement of the snowpack in the coming days, with whumpfing and shooting cracks alerting you to dangerous conditions.
Confidence
Moderate
Avalanche Summary
Natural avalanche activity has reduced with the decreased snowfall/winds.
A field team triggered a size 1 avalanche on a steep feature at tree-line. The avalanche failed down 10-15cm in the storm snow.
Artillery control on Xmas and Boxing Day had good results, with many avalanches observed in the sz 2.5-3.5 range. There was evidence of step-down avalanches on the persistent weak layers.
Be suspicious of slopes that do not appear to have avalanched in the last few days.
Snowpack Summary
South/westerly winds in the moderate range on Thursday will redistribute the recent storm snow.
A warm storm slab 55-65cm deep sits on top of weak cold, loose faceted snow. This interface is reactive in the easy to moderate range of snowpack tests, while the persistent weak layers (PWLs) below were stubborn in tests Tuesday at Fidelity.
The reaction of the PWLs to the overlying burden is the thing to watch the next few days. Dig down and test them.
Weather Summary
Temperatures will be seasonal norms as light snow continues through Saturday.
Thurs: Cloudy w/Sunny periods, isolated flurries w/trace snow, Alp high -8*C, Wind SW-25 km/h, 700m FZL
Fri: Mainly cloudy w/scattered flurries, 4cm of snow, Alp high -6*C, Wind SW 20-35 km/h, 1200m FZL
Sat: Mainly cloudy w/scattered flurries w/trace snow, Alp low -7*C, Wind SW 20-35 km/h winds, 1100m FZL
Terrain and Travel Advice
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Avalanche Problems
Storm Slabs
Heavy, warm storm slabs sit atop a weak, faceted early-winter snowpack. Steeper slopes (50*+) have likely shed this slab, but the most "fun" inclines (30-45*) may have held back from avalanching. Stick to supported, lower angle slopes with limited overhead hazard.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible - Likely
Expected Size: 1 - 2.5
Persistent Slabs
Several persistent weak layers are present in the mid to lower snowpack. These layers are still reacting in the moderate to hard range in snowpack tests. Exercise extra caution if you are planning on travelling in areas that haven't been skied yet this season.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1.5 - 3