THIS AVALANCHE ADVISORY EXPIRED ON March 25, 2016 @ 7:09 am
Avalanche Advisory published on March 24, 2016 @ 7:09 am
Issued by Dave Bingaman - Payette Avalanche Center
bottom line

The Avalanche Danger is Moderate today.  Yesterday's temperatures and clear skies produced small loose, wet and loose, dry avalanches on multiple aspects in the new snow.  Lower temperatures and cloudy skies should lessen the chance of loose avalanches except on steep, shady slopes. Lingering windslabs on leeward, upper elevation Northerly slopes may still produce human caused avalanches in isolated, windloaded areas. SW winds and additional snowfall will change conditions as the day progresses.

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
  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Winds over the last 2 weeks have done a great job adding snow to almost all aspects.  We found good sized cornices on a SE facing slope yesterday on Bruin Mountain as well as signs of windloading on multiple aspects.  While most of these slabs have settled out over the last few days, it is possible that a skier or rider may be able to trigger either a shallow or older deeper windslab on Northerly terrain where most of the recently windblown snow landed.  SW winds will be adding fresh windslabs to the problem today and will then shift to the W overnight.  Over the next few days, watch for new windslab growth on NE and E aspects.

Avalanche Problem 2: Loose Dry
  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Slopes that did not see direct sun yesterday were holding plenty of cold snow yesterday.  Temperatures today will preserve that cold snow and add a little more depth to it through the day.  Sluffs should be anticipated and managed if you are skiing in steeper terrain and especially if you are in confined or consequential terrain that would concentrate sluffing or push you over or into obstacles below. 

recent observations

We toured through upper Little French Creek and got a good look at a lot of steep terrain yesterday. Snowmobiling off trail in the morning was practically as good as it gets with plenty of light dry snow billowing over the hood. The big story was the sun and its effects on the snow.  By late morning, SE and S slopes were beginning to get warm and the surface snow was beginning to move in the form of decent sized loose, wet avalanches and  small point releases of loose, dry snow on the shadier aspects.  By late afternoon, clouds were reclaiming the sky and the snow began to settle and refreeze.  It will likely be a mixed bag of conditions today unless you are getting to the true Northerly aspects or possibly West aspects that missed the worst of the sun. We also saw several older and partially buried crowns that were probably approaching 3 feet when they happened on N and NE aspects leftover from last week's windy storms.

Remember your information can save lives. If you see anything we should know about, let us know by clicking the OBSERVATION tab at the top of the page. Or by calling/emailing PAC forecasters at 208-634-0419 or forecast@payetteavalanche.org.

If you are getting out and enjoying any spring skiing/riding we would like to know. What did you see, how was the snow? Any information is good information!

weather

Today is the beginning of the next round of storms that will continue through tomorrow night.  Falling temperatures and increasing SW and W winds will accompany the storms. Weather models are not showing a lot of potential precipitation with these storms but the Northern portion of the West Central will be favored again. Between .5 and .7 inches of liquid precip is expected which should be 5-9 inches of snow in the upper elevations. Winds will be steady in the upper teens with gusts getting close to 30 today and tonight.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Thursday Thursday Night Friday
Weather: Snow showers before noon, then rain and snow showers likely. High near 38. South southwest wind 10 to 14 mph becoming west in the afternoon. Chance of precipitation is 90%. Total daytime snow accumulation of less than a half inch possible Snow showers likely, mainly before midnight. Cloudy, with a low around 25. West wind 6 to 15 mph becoming south southeast after midnight. Chance of precipitation is 70%. New snow accumulation of less than one inch possible. Snow showers. High near 35. Calm wind becoming northwest 5 to 9 mph in the afternoon. Chance of precipitation is 90%. New snow accumulation of less than one inch possible.
Temperatures: 38 deg. F. 25 deg. F. 35 deg. F.
Wind direction: S/SW W becoming S/SE NW
Wind speed: 10-14 6-15 5-9
Expected snowfall: Trace in. Trace in. Trace in.
Granite Mountain at 7700 feet.
  Thursday Thursday Night Friday
Weather: Snow showers. Temperature falling to around 25 by 3pm. Breezy, with a southwest wind 16 to 21 mph becoming west northwest in the afternoon. Chance of precipitation is 100%. Total daytime snow accumulation of 1 to 3 inches possible Snow showers likely, mainly after midnight. Cloudy, with a low around 21. West wind 9 to 16 mph. Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible. Snow showers. High near 30. West wind 6 to 15 mph becoming north northwest in the afternoon. Chance of precipitation is 90%. New snow accumulation of 1 to 3 inches possible.
Temperatures: 30 falling to 25 later in the day deg. F. 21 deg. F. 30 deg. F.
Wind direction: SW W W
Wind speed: 16-21 9-16 6-15
Expected snowfall: 1-3 in. 1-2 in. 1-3 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.