THIS AVALANCHE ADVISORY EXPIRED ON March 10, 2018 @ 6:41 am
Avalanche Advisory published on March 9, 2018 @ 6:41 am
Issued by Dave Bingaman - Payette Avalanche Center
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Moderate Avalanche Hazard exists throughout the West Central Mountains, human triggered avalanches are possible today.  New wind slabs have formed in the last 24 hours and will continue to build through the day today.  Older wind slabs from last week's storms are still possible and may be overlying a weak layer of facets above the early February rain crust.  Watch for visual clues of where these new slabs are forming and where old wind slabs still exist.

How to read the advisory


  • Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Wind Slab
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Last week's storm left us with wind slabs on a variety of aspects, some of these slabs are resting on a weak layer of snow above the Superbowl weekend crust.  This layer has produced human triggered avalanches in the last week.  While these slabs are not widespread, their ability to propagate and the unpredictable nature of their distribution should cause you to approach steep, exposed terrain with caution today and through the next few days.  Moderate SW winds and a few inches of new snow will be creating a fresh crop of windslabs today. Watch for visual clues of wind effect and manage your slope angles as you travel in wind affected terrain.

Avalanche Problem 2: Persistent Slab
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A layer of faceted snow exists above the February 4th crust and has produced avalanches in windloaded areas over the last 2 weeks.  This layer is now buried just about 2-3 feet down in the snowpack and has shown the potential to propagate easily when triggered by a skier or rider which is what happened on the W/SW aspect of Sargent's Mt. that produced a good sized avalanche last Sunday.  In some areas, this layer bonded to the new snow above and the crust has broken down or was very weak to begin with, in other areas. possibly more prevalent in the middle elevations 6500-7500 feet,  the crust and facet combo persists and should be taken very seriously.  The only 2 ways you are going to insure your safety are by either digging in and finding out if this layer is present where you are riding or skiing or by avoiding slopes over 35 degrees.  You can also help minimize your risk by using good travel protocols and avoiding steep, rocky areas where the snowpack is less uniform and you are more likely to find a shallow trigger point.

advisory discussion

Conditions are variable across the forecast area right now. Our advisory is based upon a small number of observations. Please let us know what you are seeing out there whether it is deep stable snow or avalanche activity. Observations can be submitted here. 

recent observations

Check out the recent observations we recieved from the avalanche on Sargents Mt.  right outside the Brundage Ski Area Boundary.  There were 2 different avalanches that wer triggered in this easy to access area.  The larger of the 2 was not reported by the party that triggered it.  Please take the time to post your observation and avalanche pictures to the PAC, it is easy, it's quick and may help someone else stay out of trouble.

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 24 deg. F.
Max. temperature in the last 24 hours: 26 deg. F.
Average wind direction during the last 24 hours: W/SW
Average wind speed during the last 24 hours: 9 mph
Maximum wind gust in the last 24 hours: 27 mph
New snowfall in the last 24 hours: inches
Total snow depth: 59 inches
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.