THIS AVALANCHE ADVISORY EXPIRED ON February 14, 2017 @ 6:50 am
Avalanche Advisory published on February 13, 2017 @ 6:50 am
Issued by Kent May - Payette Avalanche Center
bottom line

The avalanche danger is CONSIDERABLE today above 7000 feet where human triggered avalanches are likely due to wind slabs on leeward slopes.  Below 7000 feet the danger is MODERATE due to wind slabs and loose wet avalanches being possible. Human triggered wet loose avalanches will remain a concern on steep slopes today as day time highs creep back up into the upper 30's. At 6000 feet and below 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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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 snow pack this year.  We found quite a few newly deposited wind slabs in mostly northerly terrain over the last few days, but also saw evidence of loading and cross loading 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 last week.

Large cornices have also formed on most of our ridge lines.  Cornices should be avoided right now as they are very large and and extremely unpredictable after the wet storm last week. We had a close call Saturday near Black Tip with a large cornice failure under the weight of a snowmobiler that that unknowingly  got too far out on the cornice when it broke causing him to fall. More information is in the OBSERVATION section. 

** 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 to forecast@payetteavalanche.org

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

Daytime warming is going to be the weather factor to keep in mind over the next two days. Temperatures at Granite Mountain weather station barely got below freezing last night and with temperatures climbing today to near 40 degrees, loose wet avalanches will be likely on all solar aspects. As the afternoon progresses, keep off steep slopes where snow is becoming soft due to the 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.  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

On Saturday there was a cornice fall avalanche in the backcountry near Black Tip Mountain north of McCall. It occurred when an individual, unknowingly, walked out on to a cornice and it broke ~15 feet back from the edge. When the cornice broke it caused a a slab avalanche on a steep cliff face. The individual, the cornice, as well as the slab avalanche all went down the cliff face of approximately 200 feet. When the individual came to rest he was buried up to his waist in snow on the lower angle slope below the cliff. Due to the location where the individual came to rest, rescue was extremely difficult. A big thanks goes out to McCall Fire, Lifeflight, and Two Bear Air who were assisted by two guides from C&M Backcountry Rentals in saving the life of the individual involved in the accident. 

This should serve as a reminder: never trust a cornice! Cornices can be much larger than you may believe and there is no definitive way to forecast when they will break. Stay far back. A good rule of thumb, is to only go as far out towards the edge as you can see rocks or trees sticking through the snow on the ridge line. No trees or rocks? Then don't go towards the edge. Many recreationalists as well as proffesionals have been severely injured and killed by cornice fall avalanches.

Below is a picture of the accident site. Use the two snowmobiles on the ridge line for scale. A video of the extraction provided by Two Bear Air can be watched by CLICKING HERE.

Photo credit: Lifeflight/McCall Fire

 

 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 32 deg. F.
Max. temperature in the last 24 hours: 32 deg. F.
Average wind direction during the last 24 hours: variable
Average wind speed during the last 24 hours: 3 mph
Maximum wind gust in the last 24 hours: 8 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: NA inches
weather

No new snow overnight. An inversion has been in place all night with mountain temperatures hovering around 32 this morning. 

Today sunny, with a high near 38. East wind 3 to 6 mph.

LONG TERM...Tuesday night through Sunday...Upper level ridge will hold over region through Wednesday before a system off the Pacific moves inland. Then a pattern change is in store for the remainder of the week. Precipitation is expected to spread across the region on Thursday morning, with snow levels around 9,000ft initially, lowering to 5,000-6,000ft by Thursday afternoon. A brief lull in precipitation is expected on Friday morning before another system moves onto the West Coast on Friday night. Southerly flow will develop on Saturday morning and precipitation will be favored over the southern peaks of the Boise and West Central mountains with showers in the valleys. A cold front moves through the region on Sunday night, lowering snow levels to around 3,500-4,500ft. Unsettled conditions expected to continue into next week, with mountain snow and valley rain, and temperatures near normal.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Monday Monday Night Tuesday
Weather: Patchy fog before 11am. Otherwise, sunny, with a high near 35. Light and variable wind. Patchy fog after 11pm. Otherwise, clear, with a low around 9. Light and variable wind. Patchy fog before 11am. Otherwise, sunny, with a high near 34. Calm wind.
Temperatures: high 35 deg. F. low 9 deg. F. high 34 deg. F.
Wind direction: variable variable calm
Wind speed: light light calm
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Monday Monday Night Tuesday
Weather: Sunny, with a high near 38. East wind 3 to 6 mph. Clear, with a low around 21. East southeast wind 3 to 5 mph. Sunny, with a high near 36. South wind 6 to 9 mph.
Temperatures: high 38 deg. F. low 21 deg. F. high 36 deg. F.
Wind direction: east east-southeast south
Wind speed: 3-6 3-5 6-9
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.