Storm slab depth is quite variable across the region. Regardless, storm slabs from 10 to 50 cm in depth are likely to remain sensitive to human triggering. Avoid wind exposed features as strong to extreme winds have likely created deep stiff slabs.
A buried rain crust is widespread in the region. The snowfall from this storm could be enough to wake up this deeper instability, especially in the central and northern portions of the region.
Storm totals across the region vary from just a few cm to more than 50 cm. Careful with the new storm snow, especially at upper elevations. Large human triggered storm slabs are likely. The new snow may be resting on surface hoar and facets which could set up a scenario where storm slabs remain surprisingly touchy.
The full brunt of the frontal wave is now in northwest B.C, this front is expected to remain stalled over the region through Sunday night before giving way to a brief window of high pressure Monday afternoon.
SUNDAY NIGHT: Freezing level peaking at 1500 m, strong to extreme south/southwest wind, 8 to 15 cm of snow expected.
MONDAY: Scattered cloud cover, freezing level around 500 m, moderate to strong west wind, 1 to 5 cm of snow expected. 5 to 10 cm of snow possible Monday Night.
TUESDAY: Overcast, freezing level climbing, potentially as high as 1400 m in the afternoon, strong to extreme southwest wind, 5 to 10 cm of snow possible.
WEDNESDAY: Broken cloud cover, freezing level potentially peaking as high as 1800 m in the afternoon, strong to extreme south/southwest wind, 5 to 10 cm of snow possible.
Observations are very limited at this time. A variable amount of new snow and wind have impacted the region and storm slabs are forming on many slopes.
The central portion of the region received almost 50 cm of snow Saturday into Saturday night around Bear Pass, there, a natural avalanche cycle may well be in progress.
Closer to Terrace there is about 10 of new snow as of Sunday afternoon. Watch for the formation of fresh storm slabs at and above treeline. Below treeline it's thought that the total depth of snow is only just reaching threshold for avalanches, but observations like this from Shames show us that avalanches in the trees are possible at this time.
Last Tuesday, a large (size 2.5) avalanche was triggered with explosives in the northern part of the region. This avalanche failed on weak snow around the crust at the bottom of the snowpack, which is a layer worth monitoring in parts of the region as the season progresses.
Careful with the new storm snow at upper elevations. Large human triggered storm slabs are possible. The new snow may be resting on surface hoar and facets which could set up a scenario where storm slabs are surprisingly touchy.
The central portion of the region near Bear Pass picked up almost 50 cm Saturday night with strong to extreme south wind. Not much snow fell around Terrace and winds were mostly light in the south.
So, the depth of storm snow is quite variable throughout the region.
We're learning that the early November crust is widespread, even in the alpine and treeline elevations. You should be able to find it 50 to 120 cm below the surface.
The total snowpack depth is roughly 100 to 150 cm at upper treeline and alpine elevations. The bottom of the snowpack consists of several thick crusts. There could be weak snow developing around these crusts in colder inland parts of the region.
