Avalanche Forecast

Expect widespread wet avalanches. If significant rain totals occur, very large natural avalanches could run long distances to their historic runouts. You will need to be extra cautious and watch for any overhead avalanche paths where avalanches could run to lower elevation slopes.

Rain falling on dry snow is the perfect combination for large and destructive wet avalanches. Some may be very large and destructive enough to break mature trees. You will definitely see loose wet avalanches at low elevations and you may see very large wet slabs extending to near treeline. There is much uncertainty around wet slab avalanches and they are very hard to predict. For certain, they can be very large and dangerous.

Release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. They generally move slowly, but can contain enough mass to cause significant damage to trees, cars or buildings. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.

Travel when the snow surface is colder and stronger. Plan your trips to avoid crossing on or under very steep slopes in the afternoon. Move to colder, shadier slopes once the snow surface turns slushly. Avoid steep, sunlit slopes above terrain traps, cliffs areas and long sustained steep pitches.

Several loose wet avalanches, and lots of pinwheels and roller balls.

Loose wet avalanches occur where water is running through the snowpack, and release at or below the trigger point. Avoid terrain traps such as cliffs, gullies, or tree wells. Exit avalanche terrain when you see pinwheels, roller balls, a slushy surface, or during rain-on-snow events.

Warm heavy snow will fall on drier snow from the past couple days. Storm slabs will be easy to trigger and could be 2 feet deep. Avalanches at upper elevations could easily entrain wet heavy snow as they run onto lower slopes becoming more dangerous and destructive. You can find a slick, recently buried interface 2-3 feet below the surface that formed around the MLK weekend. This could also serve as a bed surface for avalanches to slide on. Expect drifts to form in exposed terrain at upper elevations from southwesterly winds.

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.