THIS AVALANCHE ADVISORY EXPIRED ON March 25, 2018 @ 6:58 am
Avalanche Advisory published on March 24, 2018 @ 6:58 am
Issued by Dave Bingaman - Payette Avalanche Center
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The Avalanche Hazard is MODERATE today throughout the West Central Mountains.  Cooling temperatures following Thursday's rainy warmup have started to stabilize and refreeze the snowpack. The upper elevations have already seen a significant refreeze while middle and lower elevation slopes are still in the process of a solid refreeze.  Shallow, stiff wind slabs may be encountered on upper elevation, wind exposed terrain.  

How to read the advisory


  • Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Loose Wet
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It is still possible to trigger loose/wet avalanches today.  If the sun pops out, the likelihood of natural or human triggered wet slides will rise, especially on steeper, rocky slopes that are tilted toward the sun. Loose/wet avalanches tend to follow the sun throughout the day during springlike conditions;  E/SE slopes will see the sun early in the morning, potential for natural avalanches will begin here and continue throughout the day to S then SW slopes.  Lower elevation slopes are going to take a few more cold nights to completely refreeze as temperatures were still hovering near freezing early this morning.

Here is a photo of an East facing slope near Fisher Saddle that shows examples of classic loose/wet slides that occurred between Thursday and Friday.   Even small wet slides pack a big punch, once you get your skis or sled stuck in the debris, it is very difficult to get out.  If you are in steeper terrain and you are not riding on a firm crust, be aware of the terrain below you.  Don't let one of these small slides drag you trough rocky,  or treed areas or even worse over cliffs or into gullies.

 

Avalanche Problem 2: Wind Slab
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S, SW and W winds have been gusting with the unstable atmosphere for the last 48 hours.  Stiff wind slab or wind board has been forming in the dense snow near the ridgelines and on exposed, upper elevation terrain.  With little new snow accumulation to accompany the wind, these are still likely to be shallow but they will be dense or even firm and may crack or propagate under your skis or sled. If you notice a change in the hardness of the snow you are riding in or the snow feels hollow or drumlike, you are on a hard wind slab.

recent observations

Small, natural loose/wet avalanches were widespread throughout the last 48 hours on many steep slopes.  Cooler temperatures tonight should bring about a deeper refreeze and continue to solidify the snowpack. Yesterday saw several rounds of snow that was heavy at times but didn't accumulate much.  The upper elevations will likely have a thin dusting of new snow on the hardening crust today.

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 18 deg. F.
Max. temperature in the last 24 hours: 22 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 8 mph
Maximum wind gust in the last 24 hours: 31 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 57 inches
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.