Regions
South Coast Inland.
Storm slabs from the recent snowfall may be reactive to human-triggering. Avoid recently wind loaded areas and be prepared to back off to mellow terrain.
Weather Forecast
TUESDAY: Sunny, light northwest winds, alpine temperatures at -14.WEDNESDAY: Sunny, light north winds, alpine temperatures at -14.THURSDAY: Flurries with accumulations of 5 cm, 40-60 km/h southwest winds, alpine temperatures at -12.
Avalanche Summary
Storm slab avalanches were reported in the Duffey area on the weekend. These include a natural size 1.5 avalanche in the lee of a ridgetop, and a skier cut size 2 avalanche running on buried surface hoar on a steep northwest slope at 1760 m (see MIN report from Cerise Creek). Observations from other parts of the region are limited. Storm slabs will remain touchy on wind loaded features at higher elevations or where they exist over preserved surface hoar.
Snowpack Summary
New snow from the weekend is settling throughout the region, as 70 cm of new snow fell in the Coquihalla area, 30 cm around Manning Park, and 20 cm in the Duffey area. Snowpack tests on Sunday suggest the new snow was poorly bonded with the old snow. Overall, the storm snow is likely more reactive than in the neighboring Sea to Sky region. Several surface hoar layers have been reported in the northern part of the region, including a 30 cm deep layer with 1-2 mm decomposing surface hoar at treeline in the Duffey area, and a 60 cm deep layer with 3-5 mm surface hoar in the Pemberton area. Information on the distribution and reactivity of these layers is limited. A widespread crust can be found 70-100 cm deep throughout the region. Although this layer has been generally unreactive throughout all of the Coast Mountains, it may be possible to trigger this layer in shallow wind-affected starts zones, as recent observations in Manning Park found a mix of surface hoar and facets above the crust were reactive to snowpack tests.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.