Avalanche Forecast
Issued: Dec 26th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs.
ahanna,
Avalanche Canada
Recent storm snow will likely remain sensitive to human triggers Sunday, especially if the sun comes out. Be cautious around freshly wind loaded terrain features at upper elevations and watch for signs of loose wet avalanches at elevations where temperatures rise above freezing.
Summary
Confidence
Weather Forecast
Saturday night: Around 5 cm new snow, moderate south wind, treeline temperature -3 C, freezing level 1000 m.
Sunday: Clearing, light to moderate southwest wind, treeline temperature -2 C, freezing level rising to 1500 m.
Monday: Sunny, light northwest wind, treeline temperature 0 C, freezing level 1800 m.
Tuesday: Increasing cloud, moderate northwest wind switching to southwest, treeline temperature -3 C, freezing level 1000 m.
Avalanche Summary
On Saturday, we received reports from the North Shore mountains of several skier controlled wet loose size 1 and a skier remote size 1 wet slab on a steep unsupported roll. Some whumphing was observed but very little propagation within the storm snow.
Snowpack Summary
30-50 cm of new snow came in warm and wet before freezing levels dropped and the snow started to pile up. With a temperature trend like this, new snow is expected to adhere well to old surfaces. At 1200 m, the snow was reported to be heavy and wet on Saturday afternoon. At higher elevations where dry snow fell, strong winds are expected to have deposited deep pockets of storm slab into lee terrain features.
Around 50-100 cm of snow now overlies a hard melt-freeze crust up to around 1500 m. This layer varies so widely in depth due to the wind transport of snow as it fell over the last two storms.
The remainder of the snowpack is well-settled and hosts numerous other melt-freeze crusts which are well bonded to the surrounding snow.
Terrain and Travel
- The new snow may require another day to settle and stabilize.
- Be carefull around freshly wind loaded features.
- Brief periods of sun could quickly initiate natural avalanche activity.
Problems
Storm Slabs
30-50 cm of recent snow has been redistributed at upper elevations by overnight wind from the southwest. Storm slabs will likely be most reactive in wind loaded lees such as below ridge crests and roll overs. New snow may become increasingly sensitive to triggering when touched by the sun for the first time.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 27th, 2020 4:00PM
