Fresh snow and strong southwest wind Wednesday night into Thursday is expected to form storm slabs that may be touchy, especially in wind exposed terrain. The new snow may be sitting on a thin crust which could allow slabs to run faster and further than expected.
Fresh snow and strong southwest wind Wednesday night into Thursday is expected to form a fresh round of storm slabs that may be touchy Thursday. Watch for wind stiffened slabs in exposed terrain and keep in mind that the new snow may be sitting on a thin crust which could allow thin slabs to run faster and further than expected.
Winter Ho! The snow just keeps coming!
WEDNESDAY NIGHT: Overnight low around -12 C, strong south/southwest wind, 5 to 10 cm of snow expected.
THURSDAY: Broken cloud cover, daytime high around -8 C, strong southwest wind, 1 to 6 cm of snow expected.
FRIDAY: Broken cloud cover, daytime high around -12 C, light variable wind, trace of snow expected.
SATURDAY: Broken cloud cover, daytime high around - 16 C, moderate north/northeast wind, trace of snow possible.
Last week's storm closed the highway due to avalanches hitting the road. Avalanche activity during the storm suggests there were largely storm and wind slab problems during and immediately after the stormy period. That activity has subsided as temperatures have cooled.
With recreational traffic diverted to places like the Wheaton, our field team did similar last week and into the weekend. They observed up to size 2.5 avalanches, especially on south facing slopes, starting high on ridges and rolling well into and through the trees. See a couple of MIN posts here and here.
The term 'Wheatonesque whumpfs' is worth holding onto. Remember that a whumpf is an avalanche that tried, with one key ingredient missing -- slope angle. Whumpf the right terrain and you've converted it into the real thing, hopefully it's not rolling down ontop of you.
There has been 10 to 15 cm of recent snow at valley bottom this week and we're happy to report that the Fraser Camp Wx Station is back up and running. It looks like folks got out for some great riding this week, thanks for the MIN reports here and here! Moderate to strong southwest wind this week has formed fresh wind slabs, and more fresh snow Wednesday night into Thursday will add to that problem.
In the Wheaton Valley, there is likely a crust that has formed on the surface on steeper sunny aspects with recent sunshine. The Wheaton's continental snowpack is the kind of thing you'd find around Jasper or Kananaskis Country in the Rockies. It's a weak snowpack dominated by sugary facets and depth hoar, the icing is either layers or a fat cap of harder cohesive slab. It's an untrustworthy structure that requires really good terrain selection and travel habits, or a healthy dose of luck.
