THIS AVALANCHE ADVISORY EXPIRED ON March 22, 2020 @ 7:02 am
Avalanche Advisory published on March 21, 2020 @ 7:02 am
Issued by Dave Bingaman - Payette Avalanche Center
bottom line

The Avalanche Hazard is Low today.   You may be able to trigger isolated wind slabs in Northerly terrain, pay extra attention in gullies and other terrain features that caught wind blown snow over the last week as winds changed directions  The potential for wet, loose avalanches of various sizes will rise with the temperatures on sun affected terrain throughout the day. Remember, LOW hazard does not mean NO hazard. 

How to read the advisory


  • Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Loose Wet
  • Character ?
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    Certain
    Very Likely
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  • Size ?
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As the temperature climbs today and the sun begins to affect slopes today, you can expect natural or human triggered wet, loose avalanche conditions to increase.  Most of these will be occurring in very steep terrain at or near areas with exposed rocks.  If you are searching for steep corn filled gullies today, you will be in prime terrain for wet, loose slides.  Generally speaking, wet loose avalanches are pretty slow moving, but can easily carry you into areas or obstacles where you don't want to go.  

Fortunately, this problem is fairly easy to manage by keeping close track of the snow conditions. 

  • Is the sun directly hitting the slope you’re on or below? 
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  • Is the snow getting soft and mushy?
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  • Can the snow no longer support your weight if you step off your skis or sled?

If the answer is yes to one or more of these questions, it is time to move to cooler, shaded slopes.

Avalanche Problem 2: Wind Slab
  • Character ?
  • Aspect/Elevation ?
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    Certain
    Very Likely
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Wind slabs have been a problem for the last few weeks.  Last weekend's storm was accompanied by wind and the last few days have been fairly windy in the upper elevations.  Conditions prior to the last storm provided a variety of bed surfaces and buried layers for wind slabs to fail on. As the weather warms, the wind slab problem will diminish but remember if you are skiing shady, northerly terrain you increase your risk of finding scattered wind slabs.  Even small avalanches can have big consequences if you are in committing terrain. 

advisory discussion

If you are coming to visit the McCall, Donnelly or Cascade areas over the next few days, please be aware that we are a small, rural area with limited EMS, Medical and other resources available.  Many bars and restaurants are closed or open only for take out orders.  Both Ski Resorts are closed. We are taking the Corona Virus threat very seriously and if you are a visitor, we need you to take the precautions described by the CDC to help keep our communities safe.  You can find more info about open businesses and other community information at: https://valley-county-covid-19-response-valleycounty.hub.arcgis.com/

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 24 deg. F.
Max. temperature in the last 24 hours: 32 deg. F.
Average wind direction during the last 24 hours: W
Average wind speed during the last 24 hours: 4 mph
Maximum wind gust in the last 24 hours: 18 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: NA inches
weather

.SHORT TERM...Today through Monday night...Moisture and
instability along the Nevada border will be the focus for
scattered showers this afternoon. Otherwise, northwest flow aloft
will bring drier conditions to the remainder of southeast Oregon
and southwest Idaho, with a slight chance of an afternoon shower
in central ID. The dry northwest flow will persist through Sunday.
An upper level trough will move into the Pacific Northwest Monday
through Monday night. An increasingly moist southwest flow will
develop ahead of the trough, resulting in widespread showers by
Monday evening. Instability ahead of a cold front will also lead
to a slight chance of afternoon thunderstorms. Snow levels ahead
of the front will be around 5000 to 6000 feet which will lower to
3000 to 4000 feet Monday night with the frontal passage. Light
snow accumulations are possible, generally above 4500 feet.
Temperatures will be slightly above normal through the period.

.LONG TERM...Tuesday through Saturday...Showers and isolated
thunderstorms are anticipated for both Tuesday and Wednesday
supported by an unstable air mass in place. Temperatures will
lower rather dramatically by Tuesday and Wednesday to 5-10
degrees below normal. In addition, snow levels will drop to
around 2500-3500 feet MSL at times, allowing light accumulating
snow over the higher terrain as well as the potential for
rain/snow mix for lower elevations. A brief break in precipitation
is expected Thursday, quickly followed by the next trough and
unsettled weather for Fri/Sat. Temperatures will warm to near-
normal values for the rest of the week.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Saturday Saturday Night Sunday
Weather: Sunny, with a high near 45. Calm wind. Mostly clear, with a low around 18. Calm wind. Sunny, with a high near 45. Light and variable wind.
Temperatures: 45 deg. F. 18 deg. F. 45 deg. F.
Wind direction: Calm Calm Variable
Wind speed: Calm Calm Light
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Saturday Saturday Night Sunday
Weather: Sunny, with a high near 34. North northeast wind around 5 mph becoming calm. Mostly clear, with a low around 23. North wind around 6 mph Sunny, with a high near 32. Calm wind becoming south southwest 5 to 7 mph in the afternoon.
Temperatures: 34 deg. F. 23 deg. F. 32 deg. F.
Wind direction: NNE N SSW
Wind speed: 5 6 5-7
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.