Avalanche dangers are primarily found at higher elevations. In the south (e.g. near Squamish) the problem will be developing storm slabs while in the north (e.g. near Whistler) it's lingering wind slabs.
More snow is in the forecast, with most of it falling at high elevations in the south (e.g. near Squamish); watch steep slopes with more than 25 cm of new snow. Lingering wind slabs near Whistler may remain reactive; watch lee slopes with deeper, more cohesive pillow of snow.
On Saturday there was a widespread natural avalanche cycle in the storm snow up to size 2.5. Additionally, there were natural loose wet avalanches reported from the 1700 to 2000 m elevation band. Cornice chucks were failing (size 2) but not triggering slopes below.
On Friday, explosives control resulted in numerous storm slab avalanches to size 2. Numerous natural storm slabs including a natural cornice-triggered storm slab to size 2 were also reported.
Thanks for the observations and please continue to post your reports and photos to the Mountain Information Network. It is really helpful for forecasters!
Above around 2000 m the recent storm snow is settling. Below around 1700 m the snowpack is wet from all the rain. Between around 1700 and 2000 m is the rain-snow transition zone where melt-freeze crusts are forming.
In the dry snow zone (say 2000 m and above) strong winds formed wind slabs to the lee of ridges, ribs, and rolls.
The lower snowpack is still watched by professionals, the late December crust is down 60 to 120 cm. In the alpine, it is thin and breakable. Near the base of the snowpack, a weak facet/crust layer from mid-November can be found and remains a concern for triggering with large loads or on thin spots. In general, the snowpack is shallow.
Sunday Night: Temperatures and freezing level starts to fall with freezing level around 1000 m and snow level around 700m. Snow & rain also start to fall with around 10 mm water equivalent overnight near Squamish but only a trace near Whistler. Moderate southeast wind.
Monday: As much as 20 mm water equivalent during the day near Squamish with freezing level around 1000 m. Near the peaks that could be as much as 20 cm of snow near Squamish at higher elevations with snow depth tapering at lower elevations to where there's only a trace of wet snow around 700 m (the rain / snow line). Only a trace to a few cm near Whistler. Moderate south wind.
TuesdayNo new precipitation. Freezing level near 1000m. Light to moderate southwest wind. Cloudy or overcast.
WednesdaySnow arrives again overnight and during the day with 10 to 20 mm of water equivalency forecast. Freezing level remains steady around 1000m. Moderate to strong southeast wind.
More details can be found in the Mountain Weather Forecast.
