Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Natural avalanches unlikely.
Regions
Sea To Sky.
Spring weather and a winter snowpack makes for a power struggle. Dial back your exposure to steep terrain and cornices until temperatures drop.
Confidence
Moderate - Freezing levels are uncertain on Monday
Weather Forecast
MONDAY: Sunny and warm. Freezing level near 2700 m. Alpine high near +7. Light winds. TUESDAY: Sunny and warm. Freezing level near 1800 m. Alpine high near 0. Light winds. WEDNESDAY: Mix of sun and cloud. Freezing level near 1600 m. Alpine high near -1. Light winds. More details can be found in the Mountain Weather Forecast.
Avalanche Summary
Several large cornice falls were triggered naturally and with explosives on Saturday. Some of these triggered size 2 slabs on slopes below. There is a trend of cornice falls increasing in size and frequency as the warm weather continues. Loose wet avalanches to size 2 were also failing naturally on sunny aspects on Saturday.
Snowpack Summary
Warm temperatures are weakening surface snow layers and making cornices extra touchy. The warmth can also penetrate into more deeply buried weak layers. Minimal overnight freeze is expected, meaning warming is likely to affect the snowpack early in the day.Refrozen crusts may be found on all aspects below about 1800-2000 m; and on sunny aspects in the alpine in some places. These may break down through the day. Cold, dry and possibly wind-affected snow may still be found on various aspects in the alpine. Variable instabilities exist in recent storm snow layers. Two weak layers exist in the upper 2 m of the snowpack at and below treeline. These layers consist of surface hoar (feathery crystals) in more sheltered areas and a crust on solar aspects and on all aspects below 1600m.In the lower snowpack, a crust/facet (sugar snow) layer is now over 2 m deep. This layer may still be reactive to heavy loads (such as a cornice fall) in isolated areas.
Problems
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
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.