Early starts and early finishes are the safe way to travel in the mountains right now. The mid-summerly weather is rapidly changing conditions daily.
Weather Forecast
The heat continues, with freezing levels hovering around 3700m, intense sunshine, and calm to light winds at ridge-top. Clouds will begin to roll into the area tomorrow, with showers expected Thursday through Saturday. The freezing level will finally drop to ~2000m later on Saturday.
Snowpack Summary
The melt-freeze crust on slopes over 30* at tree-line and alpine elevations is thinner and weaker with the warm overnight temp's. This will break down rapidly with the record heat wave. Below tree-line, the snowpack is isothermal and loses all strength with the daytime warming. Northerly aspects in the high alpine still sport dry snow.
Avalanche Summary
A natural avalanche cycle late in the afternoon/evening yesterday saw deeper slabs failing, some to ground, on Tupper and MacDonald. Deep, wet slabs were also observed from S-facing aspects on Bagheera and Catamount. Expect glide-cracks to become more active, which are opening up on many slopes and can fail unpredictably.
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.
Wet Slabs
Wet Slab avalanches are the release of a cohesive layer of snow (a slab) that is generally moist or wet when the flow of liquid water weakens the bond between the slab and the surface below (snow or ground). They often occur during prolonged warming events and/or rain-on-snow events. Wet Slabs can be very unpredictable and destructive.
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.