Accumulations on our new crust could reach tipping points on Thursday. Monitor the depth and reactivity of new snow as you travel and choose terrain defensively.
A crust / facet layer from mid-November is buried 50 to 100 cm deep. Continued loading at high elevations where this layer hasn't been capped by crust keeps it a concern. Many recent destructive avalanches are associated with this problem.
15 - 40 cm of new snow will build new storm slabs (wind slabs where accumulations are less) on Thursday. Expect the greatest danger in the alpine.
No new avalanches were reported in the region Tuesday. In the adjacent Sea to Sky, ski cut and explosives-controlled slab and loose dry results to size 1.5 were running on the new atmospheric river crust.
On Monday, five natural releases in the size 2.5 to 3 range were reported on the Duffey. As was suspected with the earlier size 3's in the Hurley and Upper Lillooet, all failed on the mid-November crust.
Expect more active avalanche conditions with the next storm pulse.
15 - 40 cm of new snow should fall Wednesday night through Thursday, with the greatest amounts expected northwest of the Duffey. Dangerous storm and wind slabs should form as a result, especially where accumulations are greater.
The new snow will add to an existing 20 to 50 cm of storm snow from this week overlying a new crust and the wet snowpack below from Monday's 2100 m freezing levels and heavy rain.
A crust with facets, formed in mid-November, was buried 50 to 100 cm before the storm. Recent very large persistent slab releases have failed on this layer and continuing loading prevents us from gaining full confidence in it.
Wednesday Night
Cloudy with increasing flurries bringing 5 to 10 cm of new snow. 40 km/h southwest ridgetop wind. Treeline temperature -5 °C. Freezing level 1100 m.
Thursday
Cloudy with increasing snowfall bringing 10 to 30 cm of new snow. 30 km/h south ridgetop wind. Treeline temperature -4 °C. Freezing level 1200 m.
Friday
A mix of sun and cloud with isolated flurries and 5 to 10 cm of new snow, including overnight amounts. 20 km/h south ridgetop wind. Treeline temperature -6 °C.
Saturday
Mostly cloudy with scattered flurries and 5 - 10 cm of new snow, including overnight amounts. 20 km/h southwest ridgetop wind. Treeline temperature -6 °C.
More details can be found in the Mountain Weather Forecast.
