Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible - Likely
- Size
- 1–2.5
30-50 cm of snow sits over a weak layer of facets. This layer is expected to become increasingly reactive with warming temperatures this weekend.
Above-zero temperatures and rain destabilize the upper snowpack. Stick to conservative terrain and avoid overhead hazard.
30-50 cm of snow sits over a weak layer of facets. This layer is expected to become increasingly reactive with warming temperatures this weekend.
Loose wet avalanches will become increasingly likely as the upper snowpack becomes saturated by rain and snow melt as temperatures rise.
Over the past week, we've seen numerous avalanches on the mid January facet layer detailed in the snowpack summary. Most recent activity has been rider or explosive triggered in wind-loaded terrain features, up to size 2.5. This activity is expected to continue with additional snow/rain load this weekend.
Mixed precipitation moistens surfaces as the freezing level creeps up the mountain.
A layer of facets formed during the mid January cold snap sits 30-50 cm deep. This layer has been actively producing avalanches and is expected to continue as it is stressed by the new load.
The mid and lower snowpack is generally strong and well bonded.
Saturday night
5-10 cm of mixed precip. South alpine wind 20-40 km/h. Treeline temperature -2 °C. Freezing level 2000 m.
Sunday
5-10 mm of mixed precip, local enhancements of up to 15 mm possible, ending midday. South alpine wind 20-30 km/h. Treeline temperature +2 °C. Freezing level 2200 m.
Monday
A mix of sun and cloud. South alpine wind 40-60 km/h. Treeline temperature +3 °C. Freezing level 2500 m.
Tuesday
Mostly cloudy with flurries bringing around 5 cm of new snow. South alpine wind 40-60 km/h. Treeline temperature 0 °C. Freezing level 2000 m.
More details can be found in the Mountain Weather Forecast.