Touchy and dangerous conditions still exist in many parts of the region. With a warm, wet and windy storm on the way, the Avalanche Danger will continue to rise.
Summary
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Wednesday
Weather Forecast
Warm, wet and windy conditions will persist for most of the forecast period. Expect up to 20mm of precipitation on Wednesday with another 30mm possible Wednesday night. Winds on Wednesday will be extreme from the southwest while freezing levels will hover around 2300m. On Thursday, the region should see between 10-20cm of snow, strong southwest winds and freezing levels dropping from 1800 to about 1400m. On Friday continued snowfall is expected with accumulations ranging from 5-15cm. Winds should taper-off dramatically with freezing levels dropping to about 1000m.
Avalanche Summary
Explosives control on Sunday produced a few cornice collapses to size 2. An explosive charge also triggered a size 2 persistent slab avalanche on an adjacent alpine slope where buried surface hoar was lingering. There were also a few human involvements on Sunday. A snowboarder got too close to a recently formed cornice and triggered a size 2 cornice fall. The individual was not injured in the event. Of note, a size 1.5 persistent slab avalanche was also reported on Disease Ridge in the Spearhead Range. An individual was partially buried in the event, but was assisted quickly by their party. Looking forward, continued warm, wet and windy weather is expected to spark ongoing storm slab activity in high elevation lee terrain, but warm temperatures and loading will also increase the likelihood of waking up any lingering persistent weaknesses that were not triggered by last week's storm.
Snowpack Summary
On Wednesday, moderate to heavy snow and strong winds will continue to form deep and dense storm slabs in high elevation terrain and cause substantial cornice growth. At treeline and below, rain is forecast to further saturate the snowpack. In many areas, the early and mid-January surface hoar layers have been wiped-out by last week's storm and subsequent avalanche cycle; however, "sudden" test results and isolated persistent slab avalanches prove these interfaces should remain on your radar. These layers would be down between 80 and 150 cm deep, and still have the capacity to surprise with nasty consequences. The mid and lower snowpack is generally strong, with the exception of shallower snowpack areas that may be more faceted.
jlammers,
Avalanche Canada
