Dangerous avalanche conditions are expected.
Stick to non-avalanche terrain or very small features with limited consequences.
Persistent weak layers of surface hoar/facets or crust may be overloaded by the new snow / rain and warming temperatures.
Storm slabs will be increasingly reactive as more snow / rain accumulates and temperatures rise.
Wet loose avalanches will be likely at lower elevations during periods of rain or when the snow surface is moist or wet.
Storm slab activity in the size 1-2.5 range has been consistently reported at upper elevations across the region over the last few days. Several very large persistent slabs, up to size 3.5, have also been observed, these were largely triggered by cornice failures or icefall.
With considerable new snow/rain in the forecast, we expect to see widespread and large avalanche activity over the coming days.
Up to 55 cm of new snow may accumulate between Sunday and Monday afternoon, with potential rain and wet snow below 1500 m. The new snow will build very reactive new storm slabs.
There is a significant concern for storm slabs to step down to deeper persistent weak layers. These consist of surface hoar, facets, or a crust:
Early March layer down 80 - 120 cm. This is the primary persistent layer of concern.
Mid-Feb & Late-Jan layers down 100 - 200 cm. The lingering concern for these is in shallow or rocky areas, otherwise, these are unlikely to trigger without a significant load like a cornice failure or storm slab in motion.
Sunday Night
Cloudy with 15 to 25 cm of snow / possible rain below 1400 m. 35 to 40 km/h southwest ridgetop wind. Treeline temperature -1 °C. Freezing level around 1800 m.
Monday
Cloudy with 10 to 20 cm of snow / potential rain below 1500m. 15 to 30 km/h southwest ridgetop winds. Treeline temperature +1 °C. Freezing level rising to 2100 m.
Tuesday
Cloudy with 5 to 10 cm of snow / potential rain below 2400 m. 30 to 40 km/h south ridgetop winds. Treeline temperature +3 °C. Freezing level rising to 2600 m.
Wednesday
A mix of sun and cloud. 20 to 40 km/h southeast ridgetop winds. Treeline temperature +4 °C. Freezing level rising to 3000 m.
More details can be found in the Mountain Weather Forecast.
