UPDATED 8:00
Dangerous avalanche conditions.
Avoid overhead exposure, very large natural avalanches have the potential to run to valley bottom.
Wet loose avalanche activity can be expected from steep terrain. These avalanches could entrain significant mass and gouge to ground in shallow snowpack areas.
Rain has impacted a weak and facetted snowpack. Wet slab avalanches could fail on or step down to buried weak layers in the mid and lower snowpack resulting in very large avalanches.
If triggered, this problem will likely be the full depth of the snowpack and could run below treeline. Avoid shallow, rocky start zones.
Observations have been limited, but there is evidence of a widespread natural avalanche cycle from the past few days as rain impacted the snowpack.
There have been many large to very large (size 2-4) rider-triggered avalanches in the Purcells this week.
If poor riding quality doesn't deter you on Tuesday, keep in mind that human-triggered avalanches remain likely. Avoid overhead exposure, very large natural avalanches have the potential to run to valley bottom.
Rain has created a moist or wet upper snowpack at all elevations. A weak surface crust may have formed overnight at upper elevations.
The mid-snowpack has a couple of crusts and is generally faceted and weak above and below them.
At the base of the snowpack, weak faceted grains and depth hoar are present.
Monday Night
Cloudy with clear periods, no precipitation. Alpine wind southwest 15 to 40 km/h. Treeline temperature drops to 0 °C, freezing level 2000 m.
Tuesday
Cloudy with sunny periods and isolated showers. Alpine wind southwest 15 to 40 km/h. Treeline temperature 0 °C, freezing level 2500 m.
Wednesday
Cloudy with sunny periods and isolated showers. Alpine wind south 20 to 40 km/h. Treeline temperature 0 °C, freezing level 2500 m.
Thursday
A mix of sun and cloud, no precipitation. Alpine wind light from the south. Treeline temperature 0 °C, freezing level 1900 m
More details can be found in the Mountain Weather Forecast.
