Avalanche Forecast

Poor - Due to the number and quality of field observations

A second warm wet weather system will hit the coast on Sunday although a week ridge of high pressure will protect the interior from the brunt of this system and I expect the region will see only light flurries or showers on Sunday. Warm temperatures and moderate to strong SW winds will persist through until Tuesday

Recent snow, forecast rain, warm temperatures and high winds are a recipe for an avalanche cycle, especially when you throw in a couple of prominent weak layers. I anticipate an active cycle to continue on Sunday. Previous avalanche activity during and after the last storm system was widespread, with avalanches releasing up to size 3.5 on a variety of aspects and elevations.

Between 20 and 30 cm of new snow (and possibly rain at lower elevations) fell in the last storm which I suspect is rapidly settling into a soft slab. This new snow sits upon a moderately dense upper snowpack. A weak layer of surface hoar lies buried between 60 and 90 cm below the surface, and may sit above a crust, particularly on south-facing slopes. This "mid-January" weak layer is widespread and has been the main focus for recent avalanche activity. I suspect that it will continue to produce avalanches through the weekend as the snow pack adjusts to the recent snowfall and continued warm temperatures. The still problematic mid-December surface hoar/crust layer is now typically 90-160cm below the surface. While snowpack tests indicate this layer is gaining strength in many areas, avalanches were still noted on this layer from the last storm cycle, which suggests we still need to it into our decision making process. It has been most reactive in the 1600-1900 m elevation band.