THIS AVALANCHE ADVISORY EXPIRED ON February 13, 2017 @ 7:17 am
Avalanche Advisory published on February 12, 2017 @ 7:17 am
Issued by Dave Bingaman - Payette Avalanche Center
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The Avalanche Danger is Considerable today above 7000 feet where new windslabs have formed on mostly Northerly facing leeward slopes over the last few days.  Below 7000 feet the Danger is Moderate.  2 days of below freezing temperatures have done a great job re-freezing our very soggy snowpack.  The possibility of human caused wind slabs, and wet loose avalanches will remain on steep slopes as day time highs creep back up into the upper 30's.  

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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Our Avalanche problems have flip flopped over the last few days quite a bit with some extreme weather changes but wind seems to be the constant factor in our snowpack this year.  We found quite a few newly deposited wind slabs in mostly Northerly terrain over the last two days  but also saw evidence of loading and crossloading on E and W aspects as well. The wind slabs that have formed are mostly shallow but you may still find some high elevation areas that are harboring older and deeper wind slabs in the dense snow deposited by the wet storm that we got mid week.

Large cornices have also formed on most of our ridgelines.  Cornices should be avoided right now as they are very large and and extremely unpredictable after the wet storm this week. We had a close call yesterday near Black Tip with a large cornice failure under the weight of a snowmobiler that was taking pictures near the edge of one of these monsters when it broke. 

 You are going to see a lot of avalanche debris if you are in the mountains over the next few days,as always, please send us your pictures or observations.

Avalanche Problem 2: Loose Wet
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Our snowpack just experienced some major trauma in the form of high elevation rain.  We experienced the largest natural avalanche cycle of the winter and now the snowpack has begun healing itself with the re-freezing process that started Friday as a cold front moved in.  The upper portion of the snowpack has already formed a supportible crust in most places but you may still find some punchy, breakable areas in the middle elevations.  Avoid steeper terrain until the snowpack has completely re-frozen. 

Day time warming is going to be the next weather factor to keep in mind. Temperatures during the day will be climbing starting today and getting progressively warmer each day through the week. As we pass the freezing mark, expect to see small wet, loose avalanche activity rising especially on steep slopes that are getting direct sun.

advisory discussion

Warren Wagon snowmobile route is Closed right now.  A creek between Fisher Creek and Deep Creek flash flooded/experienced a debris flow that has blocked the road with snow and woody debris as well as cutting a deep channel through the snowmobile route and is impassible.  Acess to the Copet Creek Route is still open.  The Brush Creek route is now open and should be groomed tonight.  Lick Creek Road had water flowing across it yesterday afternoon as well near the Forest Boundary.

Snowmobiler/Snowbiker Travel Restrictions:  a quick reminder that the Granite Mountain Area Closure is now in effect, 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, 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").  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.

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. 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

If you are out in the mountains right now, you will see the aftermath of the warm storm that rolled through the West mid week.  A widespread natural wet avalanche cycle occurred on steep terrain and several large slab avalanches failed in windloaded Northerly terrain.  If you see large avalanches, take the time to note the location and send us a picture.  

Yesterday, McCall Fire and Rescue assisted by riders from C&M Backcountry Rentals and Two Bear Air responded to an accident involving a large cornice failure near Black Tip that injured a rider after a long fall into steep rocky terrain where he was apparently buried by the debris of the cornice failure.  He was not on his sled but was standing on a large overhanging section of cornice at the ridgeline. We will be collecting information today and tomorrow and release details as we know more.  

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 19 deg. F.
Max. temperature in the last 24 hours: 27 deg. F.
Average wind direction during the last 24 hours: West
Average wind speed during the last 24 hours: 1 mph
Maximum wind gust in the last 24 hours: 13 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: NA inches
weather

Quiet wx for a change. Dry, cool northwest flow aloft around a low-amplitude ridge along the coast. High clouds in BC will move south into our Idaho zones tonight, and slightly moderate temps vs under clear skies. Patchy fog in the valleys tonight and Monday due to cool moist air and light winds. Little change in daytime temps through Monday, except a little colder Monday in the Lower Treasure Valley as surface inversion strengthens. Light winds.

Monday Night through Saturday...Upper level ridge will keep the area dry through Wednesday, with above normal temperatures in the mountains, and near normal in the lower valleys. The ridge begins to move east on Wednesday night, allowing southwest flow to develop. Precipitation will overspread the region on Thursday morning. Snow levels will start out initially around 8,000ft before lowering to around 6,000ft on Friday morning and 4,500ft on Saturday morning. Unsettled conditions continue through the extended period with below normal temperatures expected into the early part of next week. There is high uncertainty in snow levels beyond Saturday, as they could range from 2,000 to 5,000ft on Sunday

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Sunday Sunday Night Monday
Weather: Mostly sunny Partly cloudy Sunny
Temperatures: 33 deg. F. 8 deg. F. 33 deg. F.
Wind direction: Calm Calm Calm
Wind speed: 0 0 0
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Sunday Sunday Night Monday
Weather: Mostly sunny Partly cloudy Sunny
Temperatures: 31 deg. F. 18 deg. F. 38 deg. F.
Wind direction: W/SW W Variable
Wind speed: 6-15 around 8 Light
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.