THIS AVALANCHE ADVISORY EXPIRED ON January 20, 2017 @ 6:17 am
Avalanche Advisory published on January 19, 2017 @ 6:17 am
Issued by George Halcom - Payette Avalanche Center
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The avalanche danger is Condiserable above 6000 feet. Last night up to a foot of new snow came in with Southwest winds around 20 MPH...resting on buried surface hoar. 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.  Below 6.000 feet. the avalanche danger is Moderate. 

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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Over the last 24 hours, Southwest winds have gusted around 20 miles an hour pushing around the new foot of snow into Northern aspets, creating fresh wind slab avalanche hazard that could break up to 2 feet deep. Wind slabs have been lingering on the Northern half of the compass above 7000 feet. While these older 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 both old and new wind 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, and still so no artificial/ human triggers have been applied yet.  

Watch out for some of the typical warning signs: rounded, pillowy, sculpted terrain is the norm throughout the northerly terrain.

Avalanche Problem 2: Storm Slab
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In the last 24 hours, the mountains have picked up around a foot of new snow, and temperatures have been warmer, just below freezing in Long Valley, and in the upper elevations. The new snow should consoloidate quickly, and bond with the old snow fairly well, except in areas that have been protected from the wind where surface hoar got buried during the storm. Buried surface hoar can linger, and be hard to predict exactly where it remains...good travel protocols and giving avalanche terrain big respect is going to be important today.

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)

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

Yesterday, near Twin Peaks, in an area sheltered from the wind, we were able to find buried surface hoar under 2 inches of new snow in our pit. 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. 

***We now have up to a foot on top of this weak layer!

 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 24 deg. F.
Max. temperature in the last 24 hours: deg. F.
Average wind direction during the last 24 hours: Southwest
Average wind speed during the last 24 hours: 8 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 Thursday, January 19, 11:00am

Area Forecast Discussion National Weather Service Boise ID 324 AM MST Thu Jan 19 2017

Today through Friday...Winter storm which brought significant snow to portions of SE Oregon and SW Idaho, along with areas of freezing rain and sleet, will wind down today. Another round of precipitation moved into the region this morning, with reports of snow and rain, although there may be pockets of freezing rain and/or sleet. A portion of the Treasure Valley from Caldwell to Mountain Home warmed to above freezing and thus any additional precipitation will be rain, possibly mixed with snow at times, today. Little to no additional snow accumulations are expected in this area. The inversion remains locked in the Lower Treasure Valley around Ontario where additional light snow accumulations will occur before tapering off later this morning. The Western Magic Valley will likely see an additional 1-3 inches before tapering off this afternoon. The remainder of the warning and advisory areas will likely see another 1-3 inches as well before ending by late morning or early afternoon. The upper trough will move through tonight accompanied by a chance of snow showers mainly over the higher terrain. The next Pacific trough will spread snow into SE Oregon on Friday. There may be enough snow accumulations to justify a Winter Weather Advisory for Harney County and possibly Malheur County. Winds will increase ahead of the trough, becoming generally Southeast 10 to 20 mph, with gusts to 30 mph east of Boise.

LONG TERM...Friday night through Wednesday...GFS and ECM in very good agreement through Wednesday. Next Pacific storm comes in Friday night and Saturday with several inches more snow throughout the region. Brief clearing Saturday night ahead of another strong Pacific frontal system with valley rain/snow and mountain snow Sunday, followed by more snow showers Sunday night through Monday night as the Pacific upper low also comes in. Clearing and colder Tuesday and Wednesday under dry northerly flow aloft behind the departing upper low. After that a pattern with models showing a strong upper ridge along the coast with drying and warming for our area.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Thursday Thursday Night Friday
Weather: Snow. High near 33. South wind 3 to 6 mph. Chance of precipitation is 80%. New snow accumulation of less than one inch possible. A 30 percent chance of snow showers, mainly before 11pm. Cloudy, with a low around 15. Calm wind becoming southeast around 5 mph after midnight. New snow accumulation of less than a half inch possible. Mostly cloudy, with a high near 29. Calm wind becoming southeast around 6 mph in the afternoon.
Temperatures: High 33 deg. F. Low 15 deg. F. High 29 deg. F.
Wind direction: South Southeast Southeast
Wind speed: 3 to6 5 6
Expected snowfall: less than one in. less than one half in. 0 in.
Granite Mountain at 7700 feet.
  Thursday Thursday Night Friday
Weather: Snow. High near 29. Breezy, with a south southwest wind 15 to 20 mph decreasing to 9 to 14 mph in the afternoon. Chance of precipitation is 80%. New snow accumulation of 1 to 2 inches possible A 30 percent chance of snow showers, mainly before 11pm. Cloudy, with a low around 19. South southwest wind 8 to 13 mph. New snow accumulation of less than a half inch possible. A 20 percent chance of snow showers before 11am. Cloudy, with a high near 27. South wind 14 to 17 mph.
Temperatures: High 29 deg. F. Low 19 deg. F. High 27 deg. F.
Wind direction: Southwest South-southwest South
Wind speed: 15 to 20...9 to 14 8 to 13 14 to 17
Expected snowfall: 1 to 2 in. less than one half 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.