A wintery storm will elevate avalanche danger in high terrain this weekend.
This will be our last forecast for the season. Check out some alternative resources for spring here.
New snow and wind are forming storm slabs at upper elevations. Slabs will likely be most reactive in wind-loaded lees and where new snow sits over a crust.
Small (mostly size 1) natural and skier-triggered wind slabs were reported earlier in the week. Otherwise, no new avalanches have been observed.
Last week, large cornice failures in high north-facing alpine terrain notably did not propagate any weak layers on the slopes below. This is a good indicator of snowpack stability.
Looking forward, we're expecting to see natural avalanches within the new storm snow.
New snow falls over widespread crusty surfaces on all but high north-facing alpine terrain, where snow is dry and likely wind affected. There are no deeper concerns at this time.
Heaviest snowfall for this storm will favor areas south of Nakusp; the Goat and Valhalla ranges on Friday and Saturday and in the southern Monashees/Okanagan on Saturday night and Sunday.
Thursday night
5 to 15 cm of new snow in high terrain. 10 to 30 km/h south ridgetop wind. Treeline temperature -2 °C. Freezing level 1900 m.
Friday
5 to 10 cm of snow in high terrain. 10 to 30 km/h southeast ridgetop wind. Treeline temperature +1 °C. Freezing level 2200 m.
Saturday
10 to 25 cm of snow in high terrain. 10 to 30 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 2100 m.
Sunday
5 to 10 cm of snow overnight, then tapering through the day with another 5 cm possible. 20 to 40 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 2100 m.
More details can be found in the Mountain Weather Forecast.
