Summary
Confidence
Fair - Due to the number of field observations
Weather Forecast
Sunday is forecast for cold temps with an increase in outflow winds, especially at upper elevations. Monday: No change in sight for the next few days as the Arctic ridge of high pressure continues to dominate through the next week. Sunny skies and cold temperatures are forecast. Alpine temperatures should hover around -20., with -15 in the valley bottoms. Winds will be light to moderate from the north. A pacific frontal system will move onto the coast on Wed. or Thursday next week. Timing and precipitation amounts are uncertain at this time.
Avalanche Summary
No recent reports of avalanches. Storm slab avalanches may be triggered by additional loads like skiing/riding. These avalanches may be large and destructive. The forecast cold temperatures will slow down bonding processes and promote surface facetting and surface hoar growth in protected locations
Snowpack Summary
Wind slabs are sitting above recently buried weak layers of surface hoar on North aspects with melt/freeze crusts on solar aspects. The storm slab is still producing moderate shears on the surface hoar between 40 and 50 cm down. This slab is not well consolidated in many parts of the region and may not produce shears in snow pit tests. Widespread whumpfing has been observed in the Nelson area from tree line elevations all the way to valley bottom. There are reports of a deeply buried early season crust that formed in October, this layer is more likely to be found in the high alpine on northerly aspects.Surface facetting continues and new surface hoar growth is being reported in some areas. This will be something to watch when the weather pattern finally changes.
bcorrigan,
Avalanche Canada
