THIS AVALANCHE ADVISORY EXPIRED ON March 7, 2017 @ 5:19 am
Avalanche Advisory published on March 6, 2017 @ 5:19 am
Issued by Kent May - Payette Avalanche Center
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The avalanche danger today is CONSIDERABLE above 7000 feet due to human triggered avalanches being likely. Wind and snow from Saturday night, and more on the way today, have created new wind and storm slabs. Between 7000 and 6000 feet the danger is MODERATE due to less snow and wind. Below 6000 the danger is LOW. 

How to read the advisory


  • Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
Avalanche Problem 1: Wind Slab
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Moderate to high winds over the weekend have created a variety of wind slabs and scouring across the West Central Mountains. Most of the winds have been coming out of the south, southwest, and the west at the Granite Mountain weather station. Rapid loading was witnessed yesterday by PAC forecasters. Today, be on the lookout for wind slabs on all leeward slopes above 7000 feet. Another 3-5 inches of snow is forecasted to fall today with winds in the teen's out of the south/southwest. This will do a great job camouflaging the old wind slabs, and build a new batch on slopes in the wind zone on the north half of the compass. Clues of wind loading are small or large wind lips (cornices), pilllowy or fat looking slopes that are smooth and rounded, or any slopes that the snow feels hollow or 'drum' like.

Cornices have continued to grow and are ranging from small and tender, to large and stubborn.

Play it safe today and avoid steep, wind loaded terrain.

Avalanche Problem 2: Storm Slab
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Our mountains have picked up almost 2 feet of new snow in the last 72 hours and more is on the way. The new snow has fallen on a variety of old snow surfaces including surface hoar, wind slabs, and crusts. This mixed bag of surfaces under the new snow is making for a poor bond in some areas that did not see the affects of the wind loading. Expect human triggered avalanches on steep terrain today.  Avoid steep and committing slopes, know your surroundings, and watch your partners.  

advisory discussion

Snowmobiler/Snowbiker Travel Restrictions: Please respect these closures and other users recreating in them.  Winter Travel Map(East side). You can download the map to the AVENZA app on your phone, and know your exact location while you are out riding.  It is your responsiblity to know where closures exist on the forest.

The Granite Mountain Area Closure is in effect Jan15-March 31, please respect Snowcats operating, signed and unsigned closures and other users in this and nearby areas.  In addition there are other areas on the Payette National Forest that are CLOSED to snowmobile traffic including Jughandle Mt east of Jug Meadows, North of Boulder Mtn, East of Rapid Peak, North of the 20 mile drainage, Lick Creek/Lake Fork Drainage (on the right side of the road as you are traveling up canyon), and the area north of Brundage Mt Ski area to junction "V" and along the east side of Brundage and Sergeants' Mts. with the exception of the Lookout Rd( junction "S").

The Friends of the Payette Avalanche Center (FPAC) needs YOU! We are in desperate need of more user support and financial assistance. The avalanche forecast is not a guaranteed service, and is in jeopardy of dwindling down to only a couple of days a week in the near future.We have equipment that is overdue for replacement but lack the funds to purchase new gear including weather station parts and our forecast sleds.  Please help if you can by clicking the DONATE tab above. If you value this life saving information, make a donation or help the FPAC in raising funds for the future.

recent observations

No new natural or human triggered slab avalanches have been reported over the last 24 hours.

Reports of fast moving loose dry avalanches have been witnessed and reported. These normally benign 'sluff's' can become quite large and possibly take you somewhere you don't want to be. If you do choose to travel in steep terrain today, be heads up for loose dry sluffs. 

Please take the time to report any avalanche activity that you see or trigger through this storm cycle.  You can send us an email at: forecast@payetteavalanche.org or better yet take 5 minutes and submit your observations through our website. Photos, aspect, elevation, trigger type and depth will help us get the word out and may save a life.

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 9 deg. F.
Max. temperature in the last 24 hours: 22 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 5 mph
Maximum wind gust in the last 24 hours: 23 mph
New snowfall in the last 24 hours: NA inches
Total snow depth: NA inches
weather

Last night 1 -2 inches of new snow.

Today snow showers. High near 14. Wind chill values between -3 and -10. South southwest wind 14 to 17 mph. Chance of precipitation is 80%. New snow accumulation of 3 to 5 inches possible.

Tonight snow showers, mainly before 11pm. Low around 12. Wind chill values between -3 and 2. West southwest wind 13 to 16 mph. Chance of precipitation is 80%. New snow accumulation of 3 to 5 inches possible.

Long term...Thursday night through Monday. The moist flow continues Thursday into Friday with widespread precipitation going through Friday night. A brief break in the precipitation Saturday morning before more moisture pours into the area.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Monday Monday Night Tuesday
Weather: Snow showers likely. Cloudy, with a high near 27. South southwest wind 7 to 10 mph. Chance of precipitation is 70%. New snow accumulation of 1 to 3 inches possible. Snow showers likely, mainly before 11pm. Cloudy, with a low around 20. South southwest wind 6 to 8 mph. Chance of precipitation is 60%. New snow accumulation of 1 to 2 inches possible. Snow showers. High near 33. South wind 6 to 10 mph. Chance of precipitation is 80%. New snow accumulation of 1 to 3 inches possible.
Temperatures: high 27 deg. F. low 20 deg. F. high 33 deg. F.
Wind direction: south-southwest south-southwest south
Wind speed: 7-10 6-8 6-10
Expected snowfall: 1-3 in. 1-2 in. 1-3 in.
Granite Mountain at 7700 feet.
  Monday Monday Night Tuesday
Weather: Snow showers. High near 14. Wind chill values between -3 and -10. South southwest wind 14 to 17 mph. Chance of precipitation is 80%. New snow accumulation of 3 to 5 inches possible. Snow showers, mainly before 11pm. Low around 12. Wind chill values between -3 and 2. West southwest wind 13 to 16 mph. Chance of precipitation is 80%. New snow accumulation of 3 to 5 inches possible. Snow showers. High near 22. Wind chill values between -1 and 5. South southwest wind 13 to 18 mph. Chance of precipitation is 90%. New snow accumulation of 4 to 8 inches possible.
Temperatures: high 14 deg. F. low 12 deg. F. high 22 deg. F.
Wind direction: south-southwest west-southwest south-southwest
Wind speed: 14-17 13-16 13-18
Expected snowfall: 3-5 in. 3-5 in. 4-8 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.