THIS AVALANCHE ADVISORY EXPIRED ON December 23, 2015 @ 6:31 am
Avalanche Advisory published on December 22, 2015 @ 6:31 am
Issued by George Halcom - Payette Avalanche Center
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Intense winds out of the South/Southwest, and heavy snow over the last 48 hours have created High avalanche hazard in the PAC Advisory Area on slopes above 7,000 feet that are steeperr than 30 degrees. Below 7,000 feet, Considerable Avalanche hazard exists, especially northern aspects that have been loaded by the wind. Give the snowpack time to adjust to all of this load, and stay out of avalanche terrain today.

How to read the advisory


  • Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.
Avalanche Problem 1: Wind Slab
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Winds out of the South/Southwest upwards of 40 MPH have pounded the PAC Advisory area along with measurable snowfall almost daily over the last week. With all of this wind and snow, we have grown some deep wind slabs on NW, N, NE, and East aspects above 7,000 feet---travel in wind loaded Avalanche terrain is not recommended today. Below 7,000 feet, and on other aspects that were not loaded by the wind have Considerable hazard, and deserve careful evaluation and respect today...take the time to look for clues as to which way the wind has been loading the snow, and stay out from under, and off of terrain steeper than 30 degrees. Gullies and other terrain features may receive cross loading and abnormal loading patterns due to local terrain features. 

Avalanche Problem 2: Storm Slab
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Our local Ski Resort, Brundage is reporting 46 inches of new snow in the last 7 days at the base area at approximately 6,000 feet. All of this snow coming into our Advisory area so quickly has a hard time becoming cohesive with the existing snowpack which makes for tender soft slabs on all aspects. While not as deadly as hard slabs, these soft slabs definitely deserve respect. Stay away from slopes over 30 degrees where these soft slabs will be likely. Time will heal/bond the new snow to the old snow. Conservative decision making and travel are essential today!

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Tuesday Tuesday Night Wednesday
Weather: Scattered snow showers. Mostly cloudy, with a temperature rising to near 26 by noon, then falling to around 18 during the remainder of the day. Southwest wind 3 to 8 mph. Chance of precipitation is 40%. Total daytime snow accumulation of less than one inch possible Snow showers, mainly after 11pm. Temperature rising to around 23 by 4am. Southwest wind 5 to 8 mph becoming south southeast in the evening. Chance of precipitation is 80%. New snow accumulation of 1 to 2 inches possible. Snow showers likely. Cloudy, with a high near 25. Southwest wind 7 to 9 mph. Chance of precipitation is 60%. New snow accumulation of 1 to 2 inches possible.
Temperatures: HI of 26 deg. F. Low of 23 deg. F. High near 25 deg. F.
Wind direction: SW SW SW
Wind speed: 3-8 MPH 5-8 7-9
Expected snowfall: <1 in. 1-2 in. 1-2 in.
Granite Mountain at 7700 feet.
  Tuesday Tuesday Night Wednesday
Weather: Scattered snow showers. Mostly cloudy, with a temperature falling to around 15 by 4pm. Breezy, with a west southwest wind 16 to 21 mph decreasing to 9 to 14 mph in the afternoon. Chance of precipitation is 50%. Total daytime snow accumulation of 1 to 2 inches possible. Snow showers, mainly after 11pm. Temperature falling to near 13 by 8pm, then rising to around 22 during the remainder of the night. Wind chill values between zero and 8. South southwest wind 10 to 18 mph. Chance of precipitation is 90%. New snow accumulation of 1 to 3 inches possible. Snow showers likely. Cloudy, with a high near 21. West southwest wind 15 to 17 mph. Chance of precipitation is 70%. New snow accumulation of 2 to 4 inches possible.
Temperatures: High of 15 deg. F. Low of 22 deg. F. Hi near 21 deg. F.
Wind direction: W,SW S,SW W,SW
Wind speed: 16-21 MPH 10-18 15-17
Expected snowfall: 1-2 in. 1-3 in. 2-4 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.