Wind slab avalanches are possible at upper elevations in the wake of the warm storm. Expect conditions to change dramatically with elevation and aspect.
New snow has likely left unstable wind slabs on lee terrain features, especially along ridgetops. The slabs could be poorly bonded to the underlying crusts.
TUESDAY NIGHT: Cloudy with isolated flurries bring trace amounts of snow to most parts of the region and up to 5 cm along the western slopes, moderate wind from the west, treeline temperatures cool to -8 C.
WEDNESDAY: Mostly cloudy skies with some isolated flurries and trace amounts of precipitation, moderate wind from the west, treeline temperatures around -4 C with freezing level around 1500 m.
THURSDAY: Mix of sun and cloud, moderate to strong wind from the southwest, treeline temperatures up to -2 C with freezing level climbing to 1800 m.
FRIDAY: Cloudy with flurries easing off in the morning bringing up to 5 cm of new snow, light wind from the southwest, freezing level around 1600 m.
There have been several reports of small (size 1 to 1.5) human triggered slab and loose avalanches over the past few days. These have mostly been on steep wind-loaded north and east facing slopes. Wind slabs likely grew during the stormy weather on Tuesday, and will remain possible to trigger over the upcoming days.
The most recent storm delivered 15 cm along the eastern Purcells and up to 30 cm along the western Purcells. This snow is likely settling relatively quickly, although could remain reactive in wind-affected terrain. The surface is likely moist and crusty below 1500 m. Several crusts can be found in the top 60 cm of the snowpack. Recent observations suggest the snow is generally well bonded to these crusts, but there could be isolated areas where these could be reactive so pay attention to signs of localized instability such as whumpfing or cracking.
