Avalanche Advisory published on January 31, 2017 @ 6:15 am
Issued by -
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The avalanche danger today is MODERATE on steep, wind affected slopes above 7000 feet due to human triggered avalanches being possible. Below 7000 feet the avalanche danger is LOW.  Do keep in mind that a layer of buried surface hoar is still being tracked around the advisory area. While the chances of triggering an avalanche due to this problem is low, the consequences would be high.

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
  • Character ?
  • Aspect/Elevation ?

With light to moderate winds out of the south-southwest over the last 24 hours and new snow in the forecast, new thin wind slabs have developed and will continue to develop in the upper most terrain on the north half of the compass. These new wind slabs should be manageable due to their small size and ease of being triggered. However, in steep exposed terrain, even a small wind slab could knock you off your feet.

Older wind slabs can still be found, but should be very stubborn to trigger. However, once triggered any avalanche can grow into a bigger problem if it breaks into weaker snow. Your best strategy is to simply avoid fat looking, rounded pillows of snow, especially if they feel or sound hollow like a drum.

advisory discussion

We are still tracking buried surface hoar and near surface facets that are now buried in our snowpack. These persistent grain types can awaken after being dormant for an extended period of time (hence the name persistent). While we don't have them as an avalanche problem, due keep this layer in mind as you make your travel plans for the day. The layer is most likely to be found on any slopes with a north tilt to them, in middle and upper elevations. Areas to be especially weary of are those that were not impacted by the winds (sheltered) previous to our last big load of snow.

**Before committing to skiing or riding a slope over 30 degrees on the north half of the compass today, take a moment to dig into the snow and see if a thin grey line (buried surface hoar) is buried one to two feet below the snow surface. If so, look elsewhere to ski and ride.

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.

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 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. 

recent observations

No new human or natural avalanches have seen or reported in the last 24 hours.

George toured up Black Lee drainage yesterday. In his pits he found a layer of buried graupel 35 cm from the surface. While his test results showed moderate failure potential and no propagation, this is yet another layer (isolated location possibly) in the snowpack to be on the look out for. Read his snowpack observation here. Also, we continue to find sun crust on any slopes that have a southern aspect. While the only current problem with this crust is it's ability to impact your powder skiing and riding, with new snow in the forecast this layer could become a problem in the future. 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 19 deg. F.
Max. temperature in the last 24 hours: 27 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 11 mph
Maximum wind gust in the last 24 hours: 23 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: inches

No new snow overnight. Granite Mountain weather station is reporting 19 degrees with winds blowing 11 to 19 out of the west-southwest as of 5 am. Today we will have moderate to strong winds out of the west-southwest due to the arrival of the incoming trough off of the Pacific coast. Winds will be in the 20's with gusts in the 30's. Temperatures will be in the 20's and forecasts are calling for 1-4 inches depending on the forecast and where you are in the West Central Mountains.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Tuesday Tuesday Night Wednesday
Weather: Snow. Patchy fog before noon. High near 24. South wind 6 to 8 mph. Chance of precipitation is 90%. Total daytime snow accumulation of 1 to 2 inches possible. Snow. Low around 10. Southwest wind around 6 mph becoming calm in the evening. Chance of precipitation is 80%. New snow accumulation of less than one inch possible. Snow likely, mainly after noon. Cloudy, with a high near 26. Light and variable wind. Chance of precipitation is 70%. New snow accumulation of less than one inch possible.
Temperatures: high 24 deg. F. low 10 deg. F. high 26 deg. F.
Wind direction: south southwest variable
Wind speed: 6-8 6 becoming calm light
Expected snowfall: 1-2 in. less than 1 in. less than 1 in.
Granite Mountain at 7700 feet.
  Tuesday Tuesday Night Wednesday
Weather: Snow. High near 26. Breezy, with a west southwest wind 17 to 26 mph, with gusts as high as 36 mph. Chance of precipitation is 100%. Total daytime snow accumulation of 1 to 3 inches possible. Snow. Low around 14. West wind 6 to 10 mph. Chance of precipitation is 90%. New snow accumulation of less than one inch possible. Snow, mainly after 11am. High near 21. Calm wind becoming south southwest 5 to 8 mph in the afternoon. Chance of precipitation is 80%. New snow accumulation of around an inch possible.
Temperatures: high 26 deg. F. low 14 deg. F. high 21 deg. F.
Wind direction: west-southwest west south-southwest
Wind speed: 17-26 6-10 5-8
Expected snowfall: 1-3 in. Less than 1 in. 1 in.

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.