Payette Avalanche Advisory

Avalanche Concern #1:

	Probability		Size		Trend
	Likelihood of triggering		Avalanche Size		Trend over the next 24 hours

North & South Valley The West Central Mountains saw quite a bit of avalanche activity this past weekend and early week. We received numerous reports of both natural and human triggered slides over the last days and we thank everyone who sent in observations. We have photo’s of one of the bigger slides posted below. Smaller slides continued to break out through Monday, all around the same faceted layer near 45cm’s down or roughly a foot and a half. This is the same weak layer that we’ve been talking about for weeks in our tests, but Mother Nature came in and reminded us how to really put on a show. While the majority of hazard has past, there remains a possibility of triggering this layer in isolated pockets on mid to upper elevation northeast through northwest facing slopes loaded by last week’s strong winds. This wind loaded layer may be slightly farther down slope than typical due to wind patterns. Pits at the top and bottom may not show you what’s in between on a given slope. Crown profiles have been showing a trend of starting shallow 6”, breaking out mid slope to 1 ½ -2 ½ ft deep and tapering off again towards the bottom   Due to weight and capability sledders have a better chance of triggering this layer than skiers do, but tilt the scales above 35 to 40 degrees and all bets are off.

For the time being I’m hedging my bets and staying out of wind exposed steep northerly terrain. If you chose to go into those areas expect and plan for possible slide activity.

 Here are some photos of the NE face of Granite Mountain slide. The first is the upper slope with a fracture approximately 540 meters wide, over a quarter of a mile which ran for a vertical fall of about 1500ft. The second is of the deposition zone estimated to be around 25 ft deep. (view image)  (view image) thats a snowmobile and a person on top

Avalanche Concern #2:

	Probability		Size		Trend
	Likelihood of triggering		Avalanche Size		Trend over the next 24 hours

Lower Elevation & South Valley Even with forecasted cloud cover temperatures are expected in the mid fifties near town elevations today and in the forties at mid elevations. Nightime refreezes have been poor, watch for large roller ball activity or a moistening, saturated snowpack. Move around the compass as the sun gains height in the sky, but watch the steep northerly slopes, don’t get sucked in by the shady powder sirens.

With a slight chance of rain forecasted at upper elevations wet slight conditions may occurr rapidly, especially if rain falls on colder drier snow. You'll want to move to low angle terrain and avoid slopes connected to steeper terrain.