Avalanche Forecast
Issued: Jan 13th, 2024 4:00PM
The alpine rating is Wind Slabs and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeLarge natural and rider triggered avalanches are still a concern, carefully evaluate slopes for signs of instability and be mindful of large slopes overhead.
Summary
Confidence
Moderate
Avalanche Summary
On Friday, a few large natural avalanches to size 3 on south and east aspects in the alpine were reported. Thursday, multiple large explosive controlled avalanches to size 3 were reported in the region that had impressive propagation. Wednesday, avalanche reports documented a natural storm slab cycle averaging size 1-2, with a few size 2.5 avalanches.
Snowpack Summary
Roughly 30-40 cm of new snow fell in the region on Monday and Tuesday. It buried moderately wind-affected snow in exposed areas at higher elevations and otherwise added to about 50 cm of recent storm snow. All this snow overlies a variety of old surfaces, but sheltered terrain where it may overlie preserved surface hoar, is the most concerning. Below 1600m a crust is present beneath the storm snow.
Two additional surface hoar layers in the top 2 m of the snowpack are diminishing in importance. The deeper of the two likely has a robust crust above it, below treeline. The depth of the snowpack varies greatly throughout the region and weak basal facets are present at the base of the snowpack.
Weather Summary
Saturday night
Partly cloudy. Variable alpine wind 10-40 km/h. Treeline temperature -34 °C.
Sunday
Mostly sunny. Northwest alpine wind 10-40 km/h. Treeline temperature -28 °C.
Monday
Mix of sun and cloud. Southwest alpine wind 10-60 km/h. Treeline temperature -23 °C.
Tuesday
Mostly cloudy. Southeast alpine wind 10-30 km/h. Treeline temperature -20 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
Problems
Wind Slabs
Watch for signs of slab formation in the new snow, particularly in wind-affected areas and where buried surface hoar could be preserved (think sheltered openings at mid elevations).
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Basal facets remain a real concern in steep, rocky terrain and other alpine features with thin-to-thick snowpack transitions. Recent avalanche activity tells us this problem is still lurking out there.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Jan 14th, 2024 4:00PM