THIS AVALANCHE ADVISORY EXPIRED ON February 26, 2018 @ 5:00 am
Avalanche Advisory published on February 25, 2018 @ 5:00 am
Issued by George Halcom - Payette Avalanche Center
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Natural and Human triggered Loose snow avalanches/sluffs are likely on slopes over 35 degrees. Wind slab hazard will be increasing, and may be found on upper and middle elevation, wind exposed slopes. Be careful near ridgelines and cornices that may be tender and overhanging.  Numerous natural and human caused avalanches occurred in the last 6 days, most of these failed in wind loaded areas where faceted snow was resting on a crust below.

How to read the advisory


  • Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
Avalanche Problem 1: Loose Dry
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The new snow is light and dry, and wants to move with you on slopes that are steeper than 35 degrees. The loose snow sluffs are somewhat predictable, but could easily take you into treewells, rocks and other obstacles that might not be on your to do list.  We watched them failing naturally yesterday and had many running away from our skis and sleds

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Avalanche Problem 2: Wind Slab
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Wind slab avalanche hazard has been on our radar as most of the snow that we have received has come with ideal winds and temperature regimes to create slabs that have failed naturally and which have been triggered by people. The slabs built up on top of crusts that have been exposed to cold temperatures and a mixture of graupel and facets....as we put more snow and wind over the next 24 hours the wind slab avalanche hazard will increase. Signs on the snow surface have likely been erased by the calmer light snow over the last 24 hours. Likely tender cornices are overhanging quite a bit right now and will be a great indicator of where the snow has been blowing and shaping the monsters on the ridges above slopes that have been wind loaded.

recent observations

Saturday, we toured through the Louie Lake Twin Peaks, Rapid cr, South Fork of Lake Fork zone. The new snow was very light, deep, deeper throughout the day, and had a tenancy to run in front of your sled and or skis. We were able to kick loose sluffs that wanted to move within the new snow on steep slopes greater than 35 degrees, and observed natural sluffing that was widespread along steep ridgelines. Test pits columns were failing on isolation within the upper six inches of new snow.

Disclaimer

This avalanche advisory is provided through a partnership between the Payette National Forest and the Payette Avalanche Center. This advisory covers the West Central Mountains between Hard Butte on the north and Council Mountain on the south. This advisory applies only to backcountry areas outside established ski area boundaries. This advisory describes general avalanche conditions and local variations always occur. This advisory expires at midnight on the posted day unless otherwise noted. The information in this advisory is provided by the USDA Forest Service who is solely responsible for its content.