THIS AVALANCHE ADVISORY EXPIRED ON March 1, 2017 @ 5:50 am
Avalanche Advisory published on February 28, 2017 @ 5:50 am
Issued by Kent May - Payette Avalanche Center
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The avalanche danger is CONSIDERABLE above 7,000 feet due to human triggered avalanches being likely. New snow combined with variable winds have caused a new batch of wind slabs on all leeward terrain in the upper elevations. In the middle elevations, on steep slopes that were not affected by the wind, loose dry avalanches are the primary problem and the danger is MODERATE. Below 6,000 feet where less new snow has fallen 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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Variable winds over the last few days are loading slopes and cross loading terrain features on all aspects above 7,000 feet. Winds at the Granite Mountain weather station have been out of the west, southwest, northwest, and even south-southeast (very early Monday morning). The winds have been light to moderate in speed, which is perfect to move the low density powder around with out causing the light snow to go air borne and sublimate. Today expect to find a wide range of wind slab depth and sensitivity from shallow and sensitive, to thick and stubborn. One thing that all the wind slabs will have in common is that they will be located on leeward aspects in exposed terrain above 7,000 feet. Be on the look out for any slopes that look pillowy, rippled, or fat with new snow. 

Also, keep in mind that this new round of snow is going to do a great job of camouflaging the older and stiffer wind slabs that still exist on most upper elevation terrain on the north half of the compass. If an avalanche was triggered today on the north half of the compass, it could step down into older wind slabs causing a much larger avalanche.

Below is weather data from the PAC weather station on Granite. You can get real time weather on Granite by clicking the WEATHER tab at the top of the web page.

Avalanche Problem 2: Loose Dry
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Cold temperatrues and low density snow will keep loose dry avalanches on our radar today. In steep terrain, be aware that these normally benign 'sluffs' can entrain a fair amount of snow and be dangerous if you are caught and taken into a terrain trap or over cliffs or rocks. Fortunately this problem is easy to predict and avoid. If travelling in steep terrain ( slopes over 35 degrees) use slope cuts to help mitigate the loose snow and keep the sluff below you as you travel down slope.

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 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 human triggered avalanches have been reported.

Great skiing and riding conditions exist out there right now. Stay safe and enjoy the blower powder!

If you see or trigger any avalanches while you are out, please let us know at payetteavalanche.org or use the OBSERVATION tab at the top of the website. 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 10 deg. F.
Max. temperature in the last 24 hours: 16 deg. F.
Average wind direction during the last 24 hours: west-southwest
Average wind speed during the last 24 hours: 4 mph
Maximum wind gust in the last 24 hours: 20 mph
New snowfall in the last 24 hours: NA inches
Total snow depth: NA inches
weather

Today snow showers. High near 18. Wind chill values between -6 and 4. West wind 14 to 17 mph. Chance of precipitation is 90%. Total daytime snow accumulation of 3 to 5 inches possible.

Tonight a there is a 50 percent chance of snow showers. Cloudy, with a low around 10. Wind chill values between -3 and 2. West wind 9 to 14 mph. New snow accumulation of 1 to 2 inches possible.

LONG TERM...Wednesday night through Monday...Westerly flow aloft through a weak ridge of high pressure will keep most of our area dry through Thursday night. Precipitation will be confined to the northern mountains in Baker County Oregon and west central Idaho mountains. Precipitation will begin to spread further south on Friday as an upper level trough approaches the Pacific Northwest coast. Showers across most of the area Friday night through Sunday will decrease Sunday night and Monday as the trough exits and a weak upper level ridge builds over the Intermountain Region. Snow levels near 5000 feet Friday through Saturday will lower to the valley floors on Sunday. Temperatures will be a few degrees below normal through Friday, a few degrees above normal on Saturday, then below normal again Sunday and Monday.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Tuesday Tuesday Night Wednesday
Weather: Snow showers, mainly before 11am. High near 25. South wind 9 to 11 mph becoming west in the afternoon. Chance of precipitation is 90%. Total daytime snow accumulation of around an inch possible. A 40 percent chance of snow showers. Cloudy, with a low around 17. West southwest wind 5 to 8 mph becoming calm in the evening. New snow accumulation of less than one inch possible. A 40 percent chance of snow showers, mainly before 11am. Cloudy, with a high near 29. Light south southeast wind becoming southwest 6 to 11 mph in the morning. New snow accumulation of less than a half inch possible.
Temperatures: high 25 deg. F. low 17 deg. F. high 29 deg. F.
Wind direction: south becoming west west-southwest south-southeast
Wind speed: 9-11 5-8 6-11
Expected snowfall: 1 in. less than 1 in. Less than .5 in.
Granite Mountain at 7700 feet.
  Tuesday Tuesday Night Wednesday
Weather: Snow showers. High near 18. Wind chill values between -6 and 4. West wind 14 to 17 mph. Chance of precipitation is 90%. Total daytime snow accumulation of 3 to 5 inches possible. A 50 percent chance of snow showers. Cloudy, with a low around 10. Wind chill values between -3 and 2. West wind 9 to 14 mph. New snow accumulation of 1 to 2 inches possible. A 50 percent chance of snow showers. Cloudy, with a high near 23. West wind 13 to 16 mph. New snow accumulation of 1 to 2 inches possible.
Temperatures: high 18 deg. F. low 10 deg. F. high 23 deg. F.
Wind direction: west west west
Wind speed: 14-17 9-14 13-16
Expected snowfall: 3-5 in. 1-2 in. 1-2 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.