Periods of strong solar radiation may weaken and release storm slabs on Southerly aspects where a buried crust may act as a good sliding surface. Cornices may also fall off due to solar warming.
Summary
Confidence
Fair - Timing or intensity of solar radiation is uncertain on Friday
Weather Forecast
Overnight and Friday: Unsettled convective weather is forecast to bring a few more cms of snow overnight and during the day. Amounts may be slightly enhanced in some of the up-slope areas. Alpine temperatures should drop to -14.0 overnight and the freezing level is expected to rise to about 900 metre during the day. Moderate Northwest winds should become light Northerly with moderate gusts.Saturday: A ridge of High pressure is slowly moving into the interior regions from the coast. Cloudy conditions in the morning should clear gradually during the day. There is a chance of a few flurries in the morning. Freezing levels are expected to rise to 1000 metres under clearing skies. Sunday: The ridge of High pressure is expected to continue to bring mostly clear skies and light Northerly winds to the interior ranges. Overnight alpine temperatures are forecast to be about -13.0 with the freezing level rising to 900 metres during the day. Periods of strong solar radiation are expected.
Avalanche Summary
Explosives control released storm slab avalanches that were 50-70 cms deep and up to size 2.5. Some reports of skiers controlling soft slab avalanches up to size 1.0 from immediate lee terrain features.
Snowpack Summary
The new storm slab is about 30-50 cms deep, with wind transported pockets that are about 70 cms deep. New cornice growth is reported to be poorly bonded and breaks off easily with light triggers. A weak layer of surface hoar and/or a crust is buried down about 70-120 cms in the alpine and treeline elevations. This surface hoar layer is producing variable results in snow profile tests, and continues to be a concern for professionals.
triley,
Avalanche Canada
