THIS AVALANCHE ADVISORY EXPIRED ON March 2, 2016 @ 6:41 am
Avalanche Advisory published on March 1, 2016 @ 6:41 am
Issued by George Halcom - Payette Avalanche Center
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The avalanche danger for today is LOW. Areas of  concern do exist on steep, upper elevation, leeward slopes especially on the north half of the compass where shallow wind slabs formed over the weekend, and sizeable cornices exist near ridgelines that may break off with the added weight of a rider or a skier.

 

How to read the advisory


  • Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Wind Slab
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Wind slabs can still be found in upper elevations on leeward terrain. With not much snow left for transporting, these slabs should be stabilizing and becoming less of a problem. Winds will pick up today, and into the evening tonight, transporting what snow is left and the 1-2" that we may recieve this evening. Little snow, and a bit of wind around 45-55 Mph could make for small shallow fresh wind slabs on east and northeast aspects. Keep an eye out for signs of freshly drifted snow for the fresh wind slabs, and stiff snow with a chalky surface for the older wind slabs. 

Also, be on the lookout for heavily corniced areas today. We have been seeing some big pieces failing over the past week with temperature swings.

The east/northeast face of Bruin Mt. shows some of the crossloading and Mid elevation micro loading that we saw last week.

Avalanche Problem 2: Cornice
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This winter has not had any shortage of snow, and most of the time it comes with stout winds out of the South-Southwest. All of this wind and snow does a great job of forming large cornices on our ridgelines. The cornices are quite large, and have formed long, thin lips that are overhanging, and are sensitive to added weight, and will break back farther than you think, as we witnessed yesterday while traveling a ridgeline en-route to Storm peak.

advisory discussion

We would love some of your observations! If you are getting out in the backcountry, let us know. Use the OBSERVATION tab above, or send us an email at forecast@payetteavalanche.org.

Thanks to all the ladies who came out Sunday for the annual PAC/Tamarack Ski Patrol Women's only Diva Avalanche Awareness Class! The eight women in yesterday's class learned about weather, snowpack, terrain, and the fundamentals of avalanche rescue. Kudos to the participants! 

We don't have any more formal avalanche awareness classes scheduled for the rest of this winter, however, check back next season for a full schedule aimed at all user groups!

recent observations

Yesterday, we toured out to Storm Peak in search of snow. On our way, we were challenged to keep our sleds cool in a hard and frozen snowpack....as we traveled to higher elevation, we found around 2-6 inches of new snow resting on a crust that was firmer on solar aspects. The wind did some scouring on the upper parts of the mountains, taking away all the snow down to the crust in some places. The new snow from Saturday made conditions soft as you traveled higher.

weather

It will be 10 degrees warmer today in the upper elevations with a high around 41 degrees in the upper elevations, and South-Southwest winds ramping up to 22-33 Mph with gusts as high as 47 Mph...winds will increase this evening with gusts as high as 55 Mph, laying down 1-2 inches of new snow, and a low of  around 24 degrees.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Tuesday Tuesday Night Wednesday
Weather: A chance of snow showers before 11am, then a slight chance of rain and snow showers. Cloudy, with a high near 42. South wind 7 to 11 mph. Chance of precipitation is 30%. New snow accumulation of less than a half inch possible. Showers likely, with thunderstorms also possible after 11pm. Mostly cloudy, with a low around 28. South southwest wind 10 to 13 mph. Chance of precipitation is 60% A 30 percent chance of snow showers before 11am. Partly sunny, with a high near 42. South southwest wind around 7 mph. Little or no snow accumulation expected.
Temperatures: High 42 deg. F. Low 28 deg. F. High 42 deg. F.
Wind direction: South South-Southwest South=Southwest
Wind speed: 7-11 Mph 10-13 Mph 7 Mph
Expected snowfall: less than half in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Tuesday Tuesday Night Wednesday
Weather: A chance of snow before 11am, then isolated snow showers after 11am. Cloudy, with a high near 41. Windy, with a south southwest wind 24 to 33 mph, with gusts as high as 47 mph. Chance of precipitation is 40%. New snow accumulation of less than one inch possible. Snow showers likely, mainly before 11pm. Some thunder is also possible. Mostly cloudy, with a low around 24. Windy, with a southwest wind 32 to 37 mph decreasing to 24 to 29 mph after midnight. Winds could gust as high as 55 mph. Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible. A 20 percent chance of snow showers before 11am. Partly sunny, with a high near 40. Southwest wind 13 to 16 mph.
Temperatures: High 41 deg. F. Low 24 deg. F. High 40 deg. F.
Wind direction: South-southwest Southwest Southwest
Wind speed: 24-33 Gusting to 47 Mph 32-37 Mph Gusting to 55 Mph 13-16 Mph
Expected snowfall: less than one in. 1-2 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.