Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Regions
Kootenay Boundary.
Be wary of sunny alpine slopes, the likelihood of triggering loose wet avalanches will increase as temperatures rise through the day. Reactive pockets of fresh snow may lurk around ridges and lee terrain on alpine slopes where snow remains dry.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain
Weather Forecast
MONDAY NIGHT: Mostly clear / west wind, 10 km/h / alpine low -2 C / freezing level valley bottomTUESDAY: Mix of sun and cloud with isolated flurries / southwest wind, 20-40 km/h / alpine high +3 C / freezing level 2100 mWEDNESDAY: Cloudy with sunny breaks / west wind, 25 gusting to 50 km/h / alpine high +3 C / freezing level 2300 mTHURSDAY: Rain and wet flurries, 5-15 mm / southwest wind, 30 gusting to 50 km/h / alpine high +5 C / freezing level 2700 m
Avalanche Summary
On Sunday, several small size 1 wind slabs were reactive to explosives, one size 3 wind slab avalanche was triggered with a very large explosive. Near Whitewater a skier triggered a windslab avalanche on a steep northwest aspect in the alpine. See the MIN report here.
Snowpack Summary
15-40 cm fell around the region since Saturday with flurries continuing through Monday. The new snow accumulated over a melt freeze crust on most aspects. On north-facing terrain above 2000 m, the new snow accumulated over another 15-30 cm wind-affected snow from early April. The snowpack is well settled below and snow is disappearing rapidly below treeline.Sun and rising freezing levels are warming the snowpack and settling new snow, the likelihood of loose wet avalanches will increase as heat penetrates into the snowpack.
Problems
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
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.