THIS AVALANCHE ADVISORY EXPIRED ON December 31, 2015 @ 6:10 am
Avalanche Advisory published on December 30, 2015 @ 6:10 am
Issued by George Halcom - Payette Avalanche Center
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Below 7,000 feet today the Avalanche Hazard is LOW. Above 7,000 the Avalanche Hazard is MODERATE due to the possibility of triggering a wind slab in steep terrain. These wind slabs are still present near ridge tops and in other terrain features that caught last week's blowing snow. In non-wind loaded terrain, stability is better and avalanches are possible but not likely. Exercise caution in all steep, consequential terrain.

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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 Wind slabs are still lingering in the upper elevation areas near ridge tops and in a few pockets where the 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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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

As time passes our snowpack continues to strengthen. This is great news, however, you should not let your guard down. Travel smart in the backcountry by exposing only one person at a time when on or near avalanche terrain. Wear and know how to use your beacon, probe, and shovel. 

 

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 will be the last day that we will see a chance of light flurries. Tomorrow, a high pressure will set in, bringing sunny skies to the mountains , and a solid inversion by New Year's Eve. Temperatures in the valleys will continue to be below normal with more normal temperatures in the mountains.   .

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Wednesday Wednesday Night Thursday
Weather: A 20 percent chance of snow showers before 11am. Partly sunny, with a high near 18. Wind chill values between -2 and 8. Calm wind becoming west northwest around 5 mph in the afternoon Partly cloudy, with a low around -6. Light and variable wind. Sunny, with a high near 15. Wind chill values between -4 and 6. Light and variable wind.
Temperatures: 18 deg. F. `6 deg. F. 15 deg. F.
Wind direction: WNW Variable Variable
Wind speed: 5 light Light and Variable
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Wednesday Wednesday Night Thursday
Weather: A 20 percent chance of snow showers. Mostly cloudy, with a high near 20. North northwest wind 3 to 6 mph Partly cloudy, with a low around 0. Wind chill values between -3 and -13. North wind 5 to 7 mph. Sunny, with a high near 20. Wind chill values between -8 and 2. Northeast wind around 8 mph.
Temperatures: 20 deg. F. 0 deg. F. 20 deg. F.
Wind direction: NNW N NE
Wind speed: 3-6 3-6 Around 8
Expected snowfall: 0 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.