THIS AVALANCHE ADVISORY EXPIRED ON January 19, 2017 @ 6:47 am
Avalanche Advisory published on January 18, 2017 @ 6:47 am
Issued by George Halcom - Payette Avalanche Center
bottom line

The avalanche danger is MODERATE on wind loaded, slopes above 7000 feet. Wind slabs remain a concern on upper elevation slopes with recent natural avalanches and the potential for human triggered slabs between a few inches and a few feet thick. Expect to see the avalanche danger rise quickly today with the approaching storm bringing more wind and snow.

How to read the advisory


  • Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Wind Slab
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The wind slab problem is fairly widespread on the Northern half of the compass above 7000 feet.  While these slabs are becoming less touchy, some of these slabs are resting on a variety of old snow surfaces ranging from hard wind board to loose, faceted snow.  You are likely to trigger these slabs not only at the ridgelines but in steep terrain below rock faces, in gullies or other confined terrain where the wind blown snow accumulated. 

Over the last week we have toured and traveled into some of the steepest northerly terrain and found wind slab crowns scattered across these slopes. What we also noticed is that most of these slopes that did not run on their own are still untouched by sledders or skiers still so no artificial/ human triggers have been applied yet.  

Overall, you can look at windloaded terrain right now with the great visibility and see the warning signs: rounded, pillowy, sculpted terrain is the norm throughout the northerly terrain, and these features are easy to recognize clues of where the problem areas are right now.  Remember right now, just because you are not seeing recent avalanches on some steep northerly terrain does not mean those slopes are safe...

advisory discussion

Snowmobiler/Snowbiker Travel Restrictions:  a quick reminder that the Granite Mountain Area Closure is now in effect.  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 snd Sargeant's 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)

Payette Avalanche Center is hosting another KNOW BEFORE YOU GO tomorrow night at the Payette National Forest Supervisors Office at 5:30 pm. This is a great way to learn the basics before thinking about heading into avalanche terrain.

There is still room in the Sawtooth Avalanche Center's Motorized Level 1 avalanche class in Fairfield this weekend.  You can email them at info@sawtoothavalanche.com for more information or to sign up, stop making excuses.  This is a great class, reasonably priced  with a shortened classroom session and 2 field days jam packed with useful travel, rescue and decision making information.

Remember your information can save lives. If you see anything we should know about, please participate in the creation of our own community avalanche advisory by submitting snow and avalanche conditions. It's okay if you leave some fields blank, just fill out what you know and/or submit photos. You can  also email us at  forecast@payetteavalanche.org.

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

Problem layers have grown over the last few days, and so have the precipitation forecasts for the next round of storms.  Well developed Surface Hoar and widespread development of Near Surface Facets are going to be a MAJOR concern as snow accumulates above them. Today's loud powder will be tomorrows weak layer...

Buried Surface Hoar is Public Enemy number one in the avalanche world, this fragile layer when buried is responsible for more avalanche accidents and deaths than any other type of problem.

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 20 deg. F.
Max. temperature in the last 24 hours: deg. F.
Average wind direction during the last 24 hours: south-southeast
Average wind speed during the last 24 hours: mph
Maximum wind gust in the last 24 hours: mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: inches
weather

 Winter Storm Warning until January 19, 11:00 AM MST

Area Forecast Discussion National Weather Service Boise ID 328 AM MST Wed Jan 18 2017 .

SHORT TERM...Today through Thursday...Freezing rain occurred for a few hours in Baker City and Burns before changing over to snow or a mix of freezing rain and snow. The forecast for the winter storm remains complicated, with a mixture of snow, freezing rain and rain in SE Oregon and SW Idaho through Thursday. The challenge will be locations for the freezing rain and mix of weather elements. Latest model temperatures have trended slightly lower in the lower valleys today, likely due to the colder air mass already in place this morning. New model runs suggest that the valley inversion will mix out a little later this evening in the Boise area than previously forecast. Biggest change will be lower snow amounts near the Nevada border where temperatures this afternoon will be above freezing and should remain above freezing for most of tonight. Heaviest snow amounts are still on track for areas generally north of a Burns-Ontario-Jerome line, with totals widely variable in valley locations that receive snow mixed with freezing rain and/or rain. Due to the complexity of the situation and low confidence for temperatures and location of freezing rain, will leave the winter weather headlines intact but with future modifications as conditions warrant. 

LONG TERM...Thursday night through Tuesday...Models in good agreement through the period. They show brief clearing Thursday night before the next Pacific storm comes into Oregon Friday with more snow. Storm will make only gradual eastward progress Friday but eventually it will bring several inches of new snow to all areas through Saturday morning. Dry and milder Saturday afternoon and night under narrow but relatively strong upper ridge, but the next Pacific cold front will quickly follow in with snow showers and cooler temps Sunday. Associated upper trough will come inland Monday and Tuesday with more snow showers. Models then hint at a pattern change to milder wx as an upper ridge develops along the coast Tuesday. && .AVIATION...At 2 AM MST leading edge of freezing rain/sleet/snow extended from KMYL through Hells Canyon to near KREO, shifting east. Leading edge will reach KBOI around 7 AM MST. TAF sites will have -FZRA/PL, except KMYL where SN should continue. Conditions throughout the region will be IFR or MVFR in clouds and pcpn. Surface winds generally southeast 10-20kts. Gusts to 30 kts in Baker County. Northeast winds 30 kts near KJER. Winds aloft southwesterly 20 to 25 kts at 10 kft MSL.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Wednesday Wednesday Night Thursday
Weather: Snow. High near 30. South southeast wind around 6 mph. Chance of precipitation is 100%. Total daytime snow accumulation of 3 to 5 inches possible. Snow. Low around 28. South southeast wind around 7 mph. Chance of precipitation is 90%. New snow accumulation of 2 to 4 inches possible. Snow. High near 32. South wind around 5 mph becoming calm in the morning. Chance of precipitation is 90%. New snow accumulation of less than one inch possible.
Temperatures: High 30 deg. F. Low 28 deg. F. High 32 deg. F.
Wind direction: South-southeast South-southeast South
Wind speed: 6 7 5
Expected snowfall: 3 to 5 in. 2 to 4 in. less than one in.
Granite Mountain at 7700 feet.
  Wednesday Wednesday Night Thursday
Weather: Snow. High near 31. Breezy, with a south wind 22 to 24 mph. Chance of precipitation is 100%. Total daytime snow accumulation of 5 to 9 inches possible. Snow. Temperature rising to around 33 by 11pm. Breezy, with a south wind 21 to 23 mph. Chance of precipitation is 90%. New snow accumulation of 3 to 5 inches possible. Snow. High near 32. South southwest wind 10 to 17 mph. Chance of precipitation is 80%. New snow accumulation of 1 to 2 inches possible.
Temperatures: High 31 deg. F. Low 21 deg. F. High 32 deg. F.
Wind direction: South South South-southwest
Wind speed: 22 to 24 21 to 23 10 to 17
Expected snowfall: 5 to 9 in. 3 to 5 in. 1 to 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.