THIS AVALANCHE ADVISORY EXPIRED ON January 12, 2016 @ 6:46 am
Avalanche Advisory published on January 11, 2016 @ 6:46 am
Issued by -
bottom line

The avalanche danger is LOW today on non wind affected aspects.  In steep upper elevation/wind loaded areas a skier or rider could trigger  a shallow wind slab and/or get caught in a fast moving sluff. In the upper elevations the avalanche danger is MODERATE.

How to read the advisory


  • Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Wind Slab
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You are most likely to find wind slabs (soft and hard) on or near ridgetops scattered from the E through the N and back to the SW aspects.  Visually, the areas of wind slab  will likely have a different texture and feel hollow or punchy.  In the wrong spot(shallow rocky, thin areas) these wind slabs may be resting on faceted or unconsolidated snow below and have the potential to become a nasty hard slab avalanche. This potential should be enough to keep you on your toes even though we are in a period of LOW danger. It should also be enough to keep you from skiing rocky areas that have visual evidence of recent wind effect or a much thinner snowpack. Snowmobiles are more likely to trigger this wind slab than a skier especially if you are high marking or making successive side hill runs through steep wind loaded areas. Be aware of how deep your track is digging and if you feel a sudden change in that depth, that means you have just cut through into the less consolidated snow below the more firm wind slab.

Avalanche Problem 2: Loose Dry
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A combination of a few inches of new snow earlier in the week and cold, facet forming conditions is bumping up the sluff potential right now. They  are just big enough to grab your skis and jerk you around if you stay in them.  If you are skiing or riding in steep terrain (40+ degrees), use good sluff management by performing slope cuts before committing to a steep line. If you are skiing steep, confined terrain have a plan or think about the consequences of getting pushed off course by a sluff, they have more than enough power to push you into or off of obstacles below.  

advisory discussion

Remember LOW danger does not mean no danger. Use safe travel protocols. Travel one at a time up, down, or across slopes in avalanche terrain. Have a plan when skiing/riding a line and share the plan with people in your group. 

 

recent observations

Surface Hoar is growing throughout the advisory area, and we need your help tracking it. It grows during clear, humid and calm conditions and once buried, it is a particularly thin, fragile and persistent weak layer in the snowpack, which accounts for a number of avalanche deaths each season. Luckily it is so fragile that it can also be destroyed by wind or dense/heavy snow (let's keep our fingers crossed). If you are out and see surface hoar let us know, it is important to track this layer as we move forward in the avalanche season.

 

 

weather

BRRRR...Today will start off similar to yesterday, cold. Temperatures in McCall are ranging from -4 degrees to +6 degrees at 6 AM, but similar to yesterday, the temperatures will rise significantly today with clear sunny skies. An inversion will cause temperatures in the high country to reach 30 while the valley floor will stay in the 20's and winds in the mountains will be in the teens. Clouds will come back to the area tonight with a chance of snow returning on Wednesday. 

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Monday Monday Night Tuesday
Weather: Mostly sunny, with a high near 23. Calm wind. Patchy fog. Otherwise, mostly cloudy, with a low around 11. Calm wind. A 20 percent chance of snow before noon. Patchy fog before noon. Otherwise, cloudy, with a high near 27. Calm wind.
Temperatures: High 23 deg. F. Low 11 deg. F. High 27 deg. F.
Wind direction:
Wind speed: Calm Calm Calm
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Monday Monday Night Tuesday
Weather: Mostly sunny, with a high near 30. West wind 11 to 17 mph. Mostly cloudy, with a low around 19. Blustery, with a northwest wind 17 to 22 mph decreasing to 11 to 16 mph in the evening. Cloudy, with a high near 30. Southwest wind around 15 mph.
Temperatures: High 30 deg. F. Low 19 deg. F. High 30 deg. F.
Wind direction: West Northwest Southwest
Wind speed: 11-17 11-22 15
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.