Avalanche Forecast

More new snow and warming temperatures Thursday will create an up-side-down snowpack with heavy snow over drier weaker snow. As this occurs it will be easier for you to trigger avalanches on open slopes greater than 35 degree where more than 8” of new snow has fallen. You may find wind affected snow in some locations forming firmer slabs. Give these areas a wide berth. Avalanches failing in these areas may break above you.

In some locations weak buried facets and/or surface hoar may exist. If avalanches fail on these layers they may act in surprising ways. You are most likely to find old weak snow above 4500’ and in sheltered terrain. If you experience shooting cracks, hear whumphig, or see recent large avalanches, stay out of avalanche terrain.

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.

You will see loose wet fan shaped avalanches Thursday as temperatures warm and precipitation turns to rain. The size of these avalanches will be limited by low coverage and rough terrain. Don’t let these little avalanches fool you. They can still have dangerous consequences if they push you over rocks, or into trees and gullies.

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.