THIS AVALANCHE ADVISORY EXPIRED ON March 8, 2017 @ 5:51 am
Avalanche Advisory published on March 7, 2017 @ 5:51 am
Issued by Kent May - Payette Avalanche Center
bottom line

The avalanche danger today is CONSIDERABLE above 7,000 feet due to human triggered avalanches being likely. A new round of wind and storm slabs have developed over the last 24 hours, and if today's forecasted snow and wind comes to fruition, the danger will increase at all elevations this afternoon and into tonight. Out of the wind zone in the middle elevations today we start out at MODERATE, and below 6,000 the danger will start out 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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The winds around the advisory area continue to be variable depending on location and timing, but primarily the winds over the last 24 hours have been out of the west and southwest. One thing is certain, there are wind slabs in the upper elevations and in middle elevations on leeward slopes. So, if you are traveling today above 7,000 feet, have your avalanche eyes on and be suspect of most all slopes that are not protected by the wind or completely scoured of snow. We may sound like a broken record in regards to wind slabs lately, but it is for a reason. These wind slabs are a sleeping dragon and if triggered could step down and become large enough to bury you (see picture in RECENT OBSERVATIONS section below). Watch the winds today as this next storm arrives out of the southwest, and make travel plans accordingly. 

 

Also, cornices are getting large this time of year and should not be trusted. Give them a wide berth if you’re traveling on ridgelines and limit the time you spend on slopes below monstrous, overhanging cornices.

Avalanche Problem 2: Storm Slab
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With the forecasts calling for 3-8 inches today and 4-10 inches tonight, storm slabs will be building today and tonight anywhere that the wind is not actively transporting or depositing snow. These storm slabs will be easily triggered during the height of the storm on steep slopes and abrupte convexities. Keep this in mind as you are out carving trenches today and make riding and skiing routes away from terrain traps.

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").

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

We got an observation from Sunday of a human triggered avalanche out of bounds at Tamarack. We don't have many details, but from we gather the individual was traveling out the north boundary to Full Moon Bowl. He was kicking a small cornice at the top (when done properly, an effective method of testing the slope below) and when the cornice broke, it triggered and propagated into a fairly large avalanche. Fortunately, the individual is a well seasoned backcontry traveler and tested the suspect slope before committing to skiing it.

 

If you see or trigger an avalanche please let us know. These observations are crucial to our forecasts. You can send us an email at: forecast@payetteavalanche.org or better yet take 5 minutes and submit your observations through our website. Photos, aspect, elevation, trigger type and depth will help us get the word out and may save a life.

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 11 deg. F.
Max. temperature in the last 24 hours: 14 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 2 mph
Maximum wind gust in the last 24 hours: 23 mph
New snowfall in the last 24 hours: NA inches
Total snow depth: NA inches
weather

Over the past 24 hours Brundage is reporting 5 inches of new snow and Tamarack is reporting 7 inches.

Today snow. High near 23. Wind chill values between -8 and 2. Breezy, with a south southwest wind 14 to 21 mph. Chance of precipitation is 100%. Total daytime snow accumulation of 5 to 9 inches possible.

Tonight snow. Temperature rising to around 28 by 11pm. Breezy, with a southwest wind 21 to 23 mph. Chance of precipitation is 100%. New snow accumulation of 5 to 9 inches possible.

Long term. Friday night through Tuesday the extended period remains active and wet. On Saturday morning a brief break in precipitation before the next Pacific System makes its way into the area. The West Central and Boise Mountains look like they will be hit the hardest with precipitation. 

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Tuesday Tuesday Night Wednesday
Weather: Snow. High near 32. South wind 7 to 10 mph. Chance of precipitation is 100%. Total daytime snow accumulation of 2 to 4 inches possible. Snow. Low around 30. South southwest wind 10 to 13 mph. Chance of precipitation is 100%. New snow accumulation of 1 to 3 inches possible. Snow likely before 11am, then rain and snow. High near 39. South southwest wind 9 to 11 mph. Chance of precipitation is 80%. New snow accumulation of less than a half inch possible.
Temperatures: high 32 deg. F. low 30 deg. F. high 39 deg. F.
Wind direction: south south-southwest south-southwest
Wind speed: 7-10 10-13 9-11
Expected snowfall: 2-4 in. 1-3 in. Less than .5 in.
Granite Mountain at 7700 feet.
  Tuesday Tuesday Night Wednesday
Weather: Snow. High near 23. Wind chill values between -8 and 2. Breezy, with a south southwest wind 14 to 21 mph. Chance of precipitation is 100%. Total daytime snow accumulation of 5 to 9 inches possible. Snow. Temperature rising to around 28 by 11pm. Breezy, with a southwest wind 21 to 23 mph. Chance of precipitation is 100%. New snow accumulation of 5 to 9 inches possible. Snow. High near 28. Breezy, with a southwest wind 18 to 20 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 7 inches possible.
Temperatures: high 23 deg. F. rising to 28 deg. F. high 28 deg. F.
Wind direction: south-southwest southwest southwest
Wind speed: 14-21 21-23 18-20
Expected snowfall: 5-9 in. 5-9 in. 3-7 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.