THIS AVALANCHE ADVISORY EXPIRED ON January 4, 2016 @ 5:29 am
Avalanche Advisory published on January 3, 2016 @ 5:29 am
Issued by George Halcom - Payette Avalanche Center
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The Avalanche Hazard remains MODERATE at upper elevations, above 7,000 feet where the possibility of triggering a wind slab in steep wind loaded terrain still exists. These wind slabs are scattered near ridge tops and in other terrain features that caught last week's blowing snow.  Exercise caution in all steep, consequential terrain...

In non-wind loaded terrain, below 7,000 feet, Avalanches are possible but not likely: stability is good and the Avalanche Hazard is LOW.

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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 The possibility of triggering Wind slabs is still lingering in the upper elevation areas near ridge tops and in a few pockets where blowing snow can accumulate. You will find them mostly on the North half of the compass and scattered on East and West Aspects.  

Most of these wind affected areas are going to be pretty obvious as a density change or an area of stiffer snow in the otherwise soft snow around them. Look for them below cornices, on steep roll overs, and in natural catcher's mitts like gullies or small depressions on the slope.You can also see what the wind has been doing, look for drifts, spines or areas of sculpted/scoured snow.  These visual clues are pretty obvious if you can see the terrain around you.  The wind slabs that we have been finding this week are shallow in most areas and only reactive on steeper terrain. Keep in mind that wind slabs are commonly triggered from thin areas, or edges of the slab.

Avalanche Problem 2: Loose Dry
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The Sun is helping consolidate the snowpack. Northern, shady aspects will have deeper snow. Small loose, dry avalanches or sluffs should be anticipated on large steep, steep confined slopes or on slopes with obstacles below your intended line. These small slides don't pack a lot of punch but can grab you and push you in a direction you don't want to go whether you are on a sled or skis. These slides are an indicator of how good the snow is staying in protected areas, it takes light dry snow to create a sluff.

recent observations

Our snowpack is fairly strong. We are seeing some good settlement...a great base for the beginning of January. The sun is putting crusts ont the surface, especially due South. A strong snowpack is great news, however, you should not let your guard down. Make Note: We will start to bury surface hoar, and surface facets that have formed during the recent cool, clear nights.

Travel smart in the backcountry by exposing only one person at a time when on or near avalanche terrain, especially above 7,000 feet where the wind has loaded slopes, and developed slabs. Wear and know how to use your beacon, probe, and shovel. 

  • Skiers and riders are getting into some of our more consequential terrain...make sure that you have an escape route planned if something goes wrong: if you do trigger a wind slab in a steep, wind loaded start zone, you may take a long ride into rocks, or possibly off a cliff? 

 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: no data deg. F.
Max. temperature in the last 24 hours: deg. F.
Average wind direction during the last 24 hours:
Average wind speed during the last 24 hours: mph
Maximum wind gust in the last 24 hours: mph
New snowfall in the last 24 hours: inches
Total snow depth: inches
weather

Today we will see cloudy skies in the mountains with light snow totaling around a half an inch. South winds upwards of 20MPH will make for a breezy day.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Sunday Sunday Night Monday
Weather: A 20 percent chance of snow before 11am. Cloudy, with a high near 23. Light south wind. Cloudy, with a low around 11. Calm wind. Mostly cloudy, with a high near 28. Calm wind.
Temperatures: 23 deg. F. 11 deg. F. 28 deg. F.
Wind direction: S Calm Calm
Wind speed: Light 0 0
Expected snowfall: in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Sunday Sunday Night Monday
Weather: A 30 percent chance of snow, mainly before 11am. Cloudy, with a high near 26. Breezy, with a south wind 18 to 22 mph. New snow accumulation of less than a half inch possible. Cloudy, with a low around 20. Breezy, with a south wind 15 to 23 mph. Mostly cloudy, with a high near 32. South wind around 16 mph.
Temperatures: 26 deg. F. 20 deg. F. 32 deg. F.
Wind direction: S S S
Wind speed: 18-22 15-23 16
Expected snowfall: < 1/2 in. 0 in. 0 in.
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.