Avalanche Forecast

Observations continue to be limited around the region at upper elevations, leading to a higher than normal degree of uncertainty. What we do know is that we just received a huge volume of water in a relatively short amount of time with, several natural avalanches reported up to D3 in size. We also know that the snowpack changes as you go up in elevation, particularly above ~5000 feet where precipitation was predominantly snow during the storm. If you travel near and above treeline, use caution on slopes 35 degrees and steeper, convexities, and unsupported slopes where you could trigger avalanches more easily. As temperatures continue to cool and more time passes, these avalanches will become less likely. Below ~5000 feet, rain effects are significant, creating heavy snow, decreased avalanche danger, and difficult travel conditions.

Release of a soft cohesive layer (a slab) of new snow that breaks within the storm snow or on the old snow surface. Storm-slab problems typically last between a few hours and few days. Storm-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.

You can reduce your risk from Storm Slabs by waiting a day or two after a storm before venturing into steep terrain. Storm slabs are most dangerous on slopes with terrain traps, such as timber, gullies, over cliffs, or terrain features that make it difficult for a rider to escape off the side.

Storm slabs usually stabilize within a few days, and release at or below the trigger point. They exist throughout the terrain, and can be avoided by waiting for the storm snow to stabilize.