Weather Forecast
Monday: A low pressure system over Gulf of Alaska will move onto the North Coast, sliding South. Snow amounts near 10 cm accompanied by strong ridgetop winds from the NW. Alpine temperatures rising to -3.0 and freezing levels near 900m. Tuesday: An intense warm front will continue to bring light snow amounts 5-10 cm. Ridgetop winds will switch and blow strong from the SE. Alpine temperatures near -1 and freezing levels rise to 1200 m. Wednesday: An upper ridge continues to build generally bringing dryer conditions during the day. Alpine temperatures near -4.0. Ridgetop winds blowing form the SW in the light ranges.
Avalanche Summary
No new avalanche observations have been reported.
Snowpack Summary
Accumulations adding up to 30 cm of new snow overlie a variety of old surfaces including hard wind slabs, thin and thick crusts and large surface hoar crystals which can be found in sheltered areas below treeline. Recent snowpack test results in the northern part of the region (1900 m) have shown inconsistent moderate breaks down 25 cm on the crust/facet layer from last week. The recent snow seems to be bonding and strengthening to the upper snowpack. Recent winds have shifted snow into soft and hard slabs anywhere from 25-40 cm thick on lee slopes. The early January surface hoar layer is buried down 40-80 cm and seems to be gaining strength. Reports indicate that this layer is mainly unreactive, and would require a larger trigger to set it off. The average snowpack depth at treeline is near 180 cm and the mid-pack is generally settled and strong.Dig down, and see what the snowpack reveals in your neck of the woods.
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.