THIS AVALANCHE ADVISORY EXPIRED ON March 19, 2016 @ 6:37 am
Avalanche Advisory published on March 18, 2016 @ 6:37 am
Issued by -
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The avalanche danger for today is MODERATE above 6,000 due to human triggered avalanches being possible. The areas of extra concern today are northwest through east facing aspects that have windslabs and cornices that developed last weekend. Secondly, as the sun heats up the snow surface today any solar aspects will have potential for loose wet avalanches. Below 6,000 feet the avalanche danger 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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Strong south-southwest winds last weekend combined with moderate snowfall created some dense windslabs which are still sensitive enough for a skier or snowmobiler to trigger today. Cautious and conservative decision making on windloaded terrain will be the key to staying safe today in the mountains. Windslabs of varying thickness between a few inches and 20 + inches may be found on E, NE, N, and NW aspects.  Some of these slabs have been camouflaged by recent new snow accumulations.  The only way you are going to know what is beneath the new snow is to take the time to dig down and look for weak layers before you commit to any steep slope in windloaded terrain today. Ski cuts and sled cuts can be effective tools but with a thick windslab, you may get surprised if you arer trying to assess the slope this way.  Careful snowpack evaluation is your best bet today, also easing into steeper terrain is advised before committing to any large, committing slope.   Loose, dry avalanches or sluffs will still be a factor today if you are skiing steep, upper elevation slopes where the snow has not begun to warm yet. Plan for significant sluffing if you are committing to confined or consequential terrain. Cornices have also grown with the recent winds, give these monsters a wide berth as they are breaking wider and further back than you would  normally expect.  As the temperatures increase over the next few days, Expect to see natural cornice failures occurring as the snowpack warms.

Avalanche Problem 2: Loose Wet
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After a couple of days of cold temps and cold snow, we are going to get our spring reality check as the temperatures warm rapidly over the next couple of days. The possibility of loose, wet avalanches and thin wet slabs will be increasing as a combination of rising temperatures and the sun warm the upper portion of the snowpack.  Today, watch for wet slide activity to increase later through the day with increasing temps and solar radiation. Over the next few days expect to see point release and roller ball activity spread to the E and SE aspects as early sun hits these slopes.

advisory discussion

If you find any safe powder stashes today, enjoy it! 

recent observations

Yesterday PAC Forecasters found light powder snow on northern aspects in the morning, but the warming temps were causing the surface snow to become more cohesive and 'cakey' by early afternoon. Quite a few point releases were also noted on north aspects, one of which looked to have caused a shallow wind slab to release.

weather

No new snow overnight and winds were light out of the north-northeast. A ridge of high pressure has built over the advisory area for the short term. Today will be mostly sunny with a high in the mid 30's with light south winds at 7,500 feet. Tomorrow highs in mid 40's and increasing winds...

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Friday Friday Night Saturday
Weather: Mostly sunny, with a high near 37. Calm wind becoming south around 5 mph in the afternoon. Partly cloudy, with a low around 16. South wind around 5 mph becoming calm in the evening. Mostly sunny, with a high near 46. Calm wind becoming south around 5 mph in the afternoon.
Temperatures: High 37 deg. F. Low 16 deg. F. High 46 deg. F.
Wind direction: south south south
Wind speed: 5 5 5
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Friday Friday Night Saturday
Weather: Mostly sunny, with a high near 36. South wind 5 to 7 mph. Partly cloudy, with a low around 24. South wind 6 to 8 mph. Mostly sunny, with a high near 45. South southwest wind 7 to 13 mph.
Temperatures: High 36 deg. F. Low 24 deg. F. High 45 deg. F.
Wind direction: south south south
Wind speed: 5-7 6-8 7-13
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.