Regions
Northwest Inland.
Confidence
Fair - Forecast snowfall amounts are uncertain on Saturday
Weather Forecast
The cold arctic air should begin to be pushed out of the region starting this evening. Strong northeast outflow winds may continue into the evening, and then be replaced with moderate to strong southerly winds by Friday afternoon. Coastal areas may receive 5-10 cm by Friday morning, and a further 10-20 cm during the day on Friday. Inland areas are expected to get about half as much snow during this period. Freezing levels are expected to remain near the valley bottoms in the Smithers area, and may rise to about 700 metres briefly on Friday afternoon near Terrace. Temperatures are expected to rise to about -4.0 at treeline on Friday and then drop slightly to about -7.0 at treeline on Saturday. Strong south-southwest winds on Saturday should continue on Sunday. A series of Pacific frontal systems will continue to bring precipitation over the next few days.
Avalanche Summary
No new reports of avalanches observed.
Snowpack Summary
The snowpack depth in the Smithers-Hankin area is about 250-275 cm at the upper extent of the treeline elevation band. Some surface facetting has been observed above treeline, and some surface hoar observed below treeline. Very strong northeast outflow winds have scoured north and east aspects and reduced previous cornice growth. The snow has been transported into stiff windslabs on south through west aspects. These windslabs should be stiff enough in most areas that the forecast southerly winds will not be able to re-distribute the snow. The mid-december crust has been observed to have bonded to the mid-pack in most areas, but may be found to have become facetted in areas with a shallow snowpack. The mid-pack is considered to be strong and well settled in most areas. No basal weak layers of concern have been reported.
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.