THIS AVALANCHE ADVISORY EXPIRED ON March 11, 2017 @ 7:00 am
Avalanche Advisory published on March 10, 2017 @ 7:00 am
Issued by Dave Bingaman - Payette Avalanche Center
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The Avalanche Danger is CONSIDERABLE today at all elevations due to natural avalanches being possible, and human triggered avalanches being likely.  Above freezing temperatures, heavy snowfall, rain on snow combined with steady S, SW and W moderate winds have all stressed our snowpack right to its breaking point.  1-3 ft thick wind slabs and storm slabs are the main concerns again today. Loose, wet avalanches will be a concern on all but the highest elevation slopes.

How to read the advisory


  • Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
Avalanche Problem 1: Storm Slab
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Our snowpack reached it's tipping point yesterday with warming temperatures,  heavy, dense snowfall, high elevation rain and moderate winds.  The 4 feet of new snow we received over the last week is settling rapidly under the weight of the new dense snow that has been falling for the last 2 days.  Yesterday and last night the rainline rose  to over 7500 feet.  

We have already had reports of large, natural avalanches 1-3 feet thick on wind loaded terrain and you will likely see more today as the clouds break up later in the day.  The potential for natural avalanches will decrease as temperatures come down later today and the moisture turns off but the possibility of human triggered avalanches will remain signifcant through the day today and until the snowpack has time heal itself over the next few days.  

Roller ball, pinwheels and loose, wet avalanche activity will make its mark on steep, mid and lower elevation slopes again today as well.  Avoid steep slopes that are unconsolidated or bottomless especially in gullies, creek bottoms or other terrain traps where even a small amount of debris could pile up deep.

If you see or trigger avalanches in the mountains over the next few days, please take the time to snap a picture,  note the aspect, location and elevation and send it to the PAC email at: forecast@payetteavalanche.org or submit an observation on our website.

Avalanche Problem 2: Wind Slab
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Yesterday we got a report of a large natural slide in Wong's Bowl.  East, Northeast, and Northerly slopes have had several days of windloading creating 1-3 foot wind slabs on many of the leeward slopes.  We were near the top of Wong's on the Slab Butte ridgeline and witnessed the loading and the massive cornices on the ridgetops earlier this week.  We were also able to trigger a small wind slab near the ridgeline with a cornice fall.  Additional loading, warm, dense snow and periods of rain over the last 12-18 hours added just enough weight that some of these like Wong's probably ran naturally.  Cornices are likely to fail naturally through the day today until temperatures start to cool down again and will be a great natural trigger to the wind slabs below.  Avoid slopes that have large overhanging cornices above them and give the remaining wind loaded areas some time to stabilize before you ski or sled through them.  Adding the weight of a skier or sled right now may be just the trigger it takes to push one of these slabs to its breaking point.  It's also a good idea to take note of where you are on ridgetops right now.  If you are past the last trees or rocks, you are likely on overhanging snow right where you don't want to be.

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").

Photo 1 is from the edge of the signed Brundage Mt. Ski Area  just past the Ski Area parking lot, photo 2 is of sled tracks ignoring Catski terrain signs...there is alot of snow out there folks.  Don't be "that" guy on a sled that gives sledders a bad reputation... please respect closures and other users.

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

Snotels near 6500 feet received between 2.2 and 2.5 inches of Snow Water Equivalent over the last 24 hours, that is a huge load. Temperatures this morning are in the mid to upper 30's at Secesh Summit and Brundage Mt.  The PAC weather station on Granite showed snowfall through the night and a high temperature of 33 degrees at 5am. The good news is that it does not appear that the rain/snow line went quite as high as forecasted and temperatures will begin falling later today.  Winds were pretty steady through the day yesterday and all but the highest areas received some amount of rain.  If you are looking for deep snow today, you might find deep but it won't be soft.  What we are looking at is some prime Northwest slop out there!

While we did not get a photo, we did get a great report submitted of a good sized, natural avalanche in Wong's Bowl during the day yesterday.    A big thanks to the reporting party for taking the time to submit the observation.  You can pretty much guarantee that similar slopes in other areas had similar events. If you see recent avalanches today, please take the time to submit an observation or email to the forecasters. 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 33 deg. F.
Max. temperature in the last 24 hours: 33 deg. F.
Average wind direction during the last 24 hours: WSW
Average wind speed during the last 24 hours: 13 mph
Maximum wind gust in the last 24 hours: 27 mph
New snowfall in the last 24 hours: NA inches
Total snow depth: NA inches
weather

SHORT TERM...Weak cold front currently within our CWA is moving
east-southeast and should be near the ID/NV border around noon
MST. KCBX radar at 2 AM MST showed rain associated with the
front extending from near McCall, ID, to Rome, OR. Once the
front and rain band pass skies will begin to clear. We decided
to cancel the small stream flood advisory for northern mountain
areas already. There is almost no thermal contrast across the
front and today`s highs will be about the same as yesterday.
Tonight will be colder, however, under mostly clear skies but
patchy fog will form late tonight and Saturday morning.
Saturday will start out mostly sunny but the next Pacific warm
front will come in with a chance of light rain in northern areas
Saturday afternoon. High temps Saturday will be much like today.

.LONG TERM...Saturday night through Friday...An upper level
ridge builds into the area on Sunday through Wednesday. Temperatures
should warm to about 10 degrees above normal on Tuesday and
Wednesday. By Thursday, the ridge starts to break down allowing
Pacific systems to push into the area once again, bringing unsettled
weather. Temperatures should moderate down to near normal values

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Friday Friday Night Saturday
Weather: Rain likely before 11am. Cloudy, with a high near 44. South southwest wind 8 to 11 mph. Chance of precipitation is 60%. Partly cloudy, with a low around 24. Southwest wind around 5 mph becoming calm in the evening. A 30 percent chance of showers after 11am. Increasing clouds, with a high near 44. South wind 3 to 7 mph.
Temperatures: 44 deg. F. 24 deg. F. 44 deg. F.
Wind direction: S SW S
Wind speed: 8-11 5 3-7
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Friday Friday Night Saturday
Weather: Snow likely, mainly before 11am. Cloudy, with a temperature falling to around 26 by 5pm. Breezy, with a southwest wind 14 to 21 mph. Chance of precipitation is 60%. New snow accumulation of less than a half inch possible. Partly cloudy, with a low around 25. West southwest wind 7 to 10 mph A 30 percent chance of snow showers after 11am. Increasing clouds, with a high near 33. Breezy, with a south wind 10 to 20 mph. New snow accumulation of less than one inch possible.
Temperatures: Falling to 26 deg. F. 25 deg. F. 33 deg. F.
Wind direction: SW WSW S
Wind speed: 14-21 7-10 10-20
Expected snowfall: Trace in. 0 in. Trace 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.