THIS AVALANCHE ADVISORY EXPIRED ON January 10, 2016 @ 6:16 am
Avalanche Advisory published on January 9, 2016 @ 6:16 am
Issued by Dave Bingaman - Payette Avalanche Center
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The avalanche danger is Low today on non wind loaded aspects. Remember Low Hazard does not mean no Hazard, in steep upper elevation, wind loaded areas there remains the possibility of triggering shallow wind slabs and fast moving sluffs. If traveling on high elevation, steep slopes today, evaluate the snow and terrain carefully, and use good travel protocols.

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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Our wind slab problem is like a lingering tooth ache right now.  It won't go away, but it's not too bad.  In a nutshell, you can find wind slabs in a variety of upper elevation terrain but you are not likely to trigger them in most of those areas. There are two layers that you should be aware of, one is a shallow (2-3 inch) layer that is fairly reactive when you find it but is soft enough that it disintegrates when it pops loose from the surrounding snow.  The second is a little thicker, deeper and quite a bit denser.  You are likely to find this on or near ridgetops scattered from the E through the N and back to the SW.  We have been finding pockets of this close to the ridgetops and found it to be mostly stable although it is still punchy and hollow.  In the wrong spot(think shallow rocky, thin areas) this unsupported slab still has 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 Hazard.  It should also be enough to keep you from skiing rocky areas that have visual evidence of recent wind effect. Snowmobiles are more likely to trigger this deeper 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 dry, facet forming conditions is bumping up the sluff potential right now.  Yesterday near Beaverdam Peak we found shallow, fast sluffs chasing us down the steeper terrain.  They were just big enough to grab your skis and jerk you around if you stayed in them.  If you are skiing in steeper terrain, use good sluff management. 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.

recent observations

We toured across from Lick Creek Summit yesterday and found shallow powder and easy travelling. We also found a healthy crop of fresh surface hoar growing in all but the most wind affected areas. The snow that we had earlier in the week gave us a great little recharge on the skiing and riding and also set us back up for some fast, shallow ​sluffs in the steeper terrain.

         

weather

The upper level High pressure will remain in place through mid week next week.  A series of small, weak storms will hit the west coast during this time with the possibility of some light accumulations. These storms will likely weaken and pass through Oregon and Southern Idaho.  The West Central will probably remain dry with inversions continuing to build in the valleys. Temperatures are expected to remain close to normal or just below normal over the next 7 days. Look for a  slight chance of light snow on Monday and Wednesday.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Saturday Saturday Night Sunday
Weather: Patchy dense fog before 11am. Otherwise, mostly cloudy, with a high near 26. Light and variable wind. atchy fog after 11pm. Otherwise, mostly cloudy, with a low around 8. Light and variable wind. Patchy fog before 11am. Otherwise, mostly sunny, with a high near 26. Light and variable wind.
Temperatures: 26 deg. F. 8 deg. F. 26 deg. F.
Wind direction: Variable Variable Variable
Wind speed: Light Light Light
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Saturday Saturday Night Sunday
Weather: Patchy dense fog before 11am. Otherwise, mostly cloudy. Patchy fog after 11pm. Otherwise, mostly cloudy. Patchy fog before 11am. Otherwise, mostly sunny.
Temperatures: 27 deg. F. 14 deg. F. 28 deg. F.
Wind direction: West southwest wind Southwest wind becoming light and variable West wind
Wind speed: 8 5-7 6
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.