Conditions are ripe for an impressive avalanche cycle. Thursday is a day to wait out the storm from a safe place.
Summary
Confidence
High
Weather Forecast
Tonight and Thursday: 50-90 cm of snow. The freezing level starts near 1000 m and rises to 1600-2000 m late in the day. Winds are strong from the South. Friday: A few flurries and a clearing trend. The freezing level dips slightly to 1500 m. Winds ease to light from the SW. Saturday: Cloudy with sunny breaks. The freezing level is around 1200 m and winds remain light from the W-SW.
Avalanche Summary
All signs point to a snowpack that is primed for a large and widespread avalanche cycle with the incoming "Pineapple Express Light" storm arriving on Wednesday night. Reports from the last few days include numerous natural and rider-triggered slabs up to size 2. Many of these were failing on a surface hoar layer down 40-100 cm deep, and most occurred on Northerly aspects near treeline. Many public observers are also noting signs of instability like whumpfing and cracking.
Snowpack Summary
Approximately 60-100cm of storm snow has accumulated in the last two weeks and is bonding poorly to a widespread layer of surface hoar, facets, and/or sun crust from early January. Recent snowpack tests produced clean and sudden fractures on both these weaknesses with only moderate force. Expect this layer to become very active with intense loading this week! The mid and lower snowpack is generally strong, with the exception of shallower snowpack areas that may be more faceted. At lower treeline elevations recent rains have saturated the upper snowpack. At higher elevations moderate to strong southwest winds have recently loaded lee features at treeline and in the alpine.
pmarshall,
Avalanche Canada
