The storm is moving across the interior regions tonight resulting in HIGH avalanche danger by morning. Heavy snowfall and strong winds are expected to develop new storm slabs.
Summary
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
A moist Pacific storm is moving into the region from the Southwest on Sunday. Expect strong Southwest winds overnight and 20-30 cm of new snow by Monday morning. Winds should become moderate Westerly during the day Monday with periods of snow ( 5-10 cm). Winds becoming strong Westerly Monday evening as the next pulse of moisture moves into the region bringing 20-30 cm by Tuesday morning and another 10-15 cm during the day. Warm air and strong Southwest winds are expected on Wednesday at the end of the storm. Freezing levels are expected to gradually rise from valley bottoms at the beginning of the storm up to 1200 metres on Tuesday and then up to 1600 metres on Wednesday afternoon. Western and Southern parts of the region should see more snow than Eastern and Northern areas due to the position of the cold arctic air to the East.
Avalanche Summary
Persistent slab avalanches continued to be remotely triggered on Saturday by helicopters landing on adjacent slopes and also by skiers travelling near steep un-supported terrain. Expect natural avalanche activity as a result of the developing new storm slab.
Snowpack Summary
The recent 10-20 cm of light dry snow is expected to develop into a storm slab with the forecast heavy snow and strong winds. This new storm slab is sitting on recent windslabs that developed on various aspects during a period of changing wind directions last week. The mid-December persistent weak layer of surface hoar and crust is buried down between 40-90 cm across the region, with most avalanches releasing down about 70 cm between 1700 and 2100 metres elevation. A hard rain crust with facets from early November is buried more than a metre down and is currently unreactive.
triley,
Avalanche Canada
