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GNFAC Avalanche Forecast for Mon Apr 7, 2014

Snowpack and Avalanche Discussion

Some avalanche concerns to keep in mind:

1. NEW SNOW AND WIND-LOADING

The greatest avalanche concern is new snowfall and wind-loading. The likelihood of triggering avalanches spikes during and immediately after significant snow storms. Wind loaded slopes, usually found near ridgelines, are especially dangerous. Any instability associated with the new and/or windblown snow can easily be found in the upper few feet of the snowpack. Instabilities associated with new snowfall are typically around for only a few days.

2. WET SNOW AVALANCHES

Graupel is like hail. When buried it is a temporary weak layer but tends to bond fairly in a day or two. It tends to roll down hill and pool on aprons and cones. From April 3 north of Frazier Basin: "We felt like someone could have triggered fresh wind slabs in places, especially where the graupel had pooled to a dramatic degree.  Other than that the surface snow looked and felt pretty good." Photos: B. Fredlund

Bridger Range, 2014-04-04

"The surface hoar grains were about .5-.8cm, and didn’t seem to be distributed too far down the slope into bear, maybe 2-300 vert max. The heat and solar from Tuesday broke it down lower in the valley. And it was pretty much gone on S facing aspects as we went back to the truck." Photo: L. Zukiewicz

Northern Madison, 2014-04-04