Regions
Northwest Coastal.
A week of benign weather. Watch for isolated wind slabs on a variety of aspects.
Confidence
High - The weather pattern is stable
Weather Forecast
MONDAY: Isolated flurries with trace accumulations, light south wind, alpine temperatures around -4 C.TUESDAY: Isolated flurries with trace accumulations, light northwest wind, alpine temperatures around -6 C.WEDNESDAY: Mix of sun and cloud, light northwest wind, alpine temperatures around -8 C.
Avalanche Summary
On Saturday, several small size 1 wind slabs were reported. Small loose dry avalanches running on the rain crust have also been reactive to skier traffic. Watch for isolated pockets where thicker wind slabs could produce larger avalanches.
Snowpack Summary
Clear cold weather and shifting winds have created a variety of surface conditions including isolated wind slabs, pockets of soft snow (15-25 cm deep), sun crusts, and surface hoar. A supportive rain crust exists below 1000 m. A layer of surface hoar that was buried on February 10th can be found buried 30-60 cm deep at treeline elevations and has been reactive in some recent snowpack tests. Below this layer, the snowpack is generally settled and strong. The exception is shallow snowpack areas around Bear Pass and Ningunsaw where basal facets remain an ongoing concern.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.