Lawinenlagebericht

Salmon River Mountains

Payette Avalanche Center
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Lawinengefahr

Mon
Hochgebirge
3 · Erheblich
Waldgrenze
3 · Erheblich
Unterhalb
1 · Gering
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Veraltet — dieser Lagebericht ist 6 months ago abgelaufen. Du siehst vergangene Verhältnisse, nicht den aktuellen Bericht.

Kernpunkte

The snowpack can still produce dangerously large avalanches around 2-3+ feet thick—especially in wind-drifted terrain. Reduce your odds of triggering a slide by sticking to lower-angled terrain without steep slopes above you. Avalanches may be triggered remotely—from below, above, and to the sides of steep slopes. 

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    2–2.5

    Observations of unstable snowpack tests and collapsing continue to be reported. It should be noted that these observations span from upper elevations to only the topmost portion of the middle-elevation band, above the rain/snow line from the last storm, ~7,000 feet. The lower portion of the middle-elevation band has lower avalanche hazard, but the overall rating has remained higher because of this. The problems described below are more dangerous where the wind has built thicker drifts of snow.

    1. A thick layer of surface hoar (plus or minus a crust, depending on your aspect and elevation) is buried about 2' deep. This layer formed during several days of dry weather in early February and was quickly loaded [and preserved] with some snowfall. It appears to be responsible for a large portion of the recent avalanche activity in both zones & was likely the culprit in a remotely triggered slide. 2 feet deep is the ideal triggering depth: thin enough in many areas for a human to trigger, but thick enough to produce large and dangerous avalanches. 
    2. Our well-known January drought snow is buried 3' deep or more. In contrast to the weak layer mentioned above, this layer formed over a long period (3+ weeks) and was loaded very slowly. It remains far less likely and far more difficult to trigger, unless you trigger an avalanche in the snow above it. 

    You can reduce your risk by avoiding slopes over about 35 degrees, especially those that are of rocky, wind-affected, alpine nature. Pay attention to what's below you—look for trees, rocks, gullies, and other terrain traps.

     

    (2/26/2026) 

    Two days ago, riders remotely triggered this avalanche near Frog Lake north of McCall.

Avalanche Discussion

Phew, that's a long avalanche problem description above, but some things are worth covering in detail. Some other FAQ's regarding the current avalanche conditions...

Q: Where are conditions most dangerous?A: The last storm produced widespread avalanche activity, with natural and human-triggered avalanches occurring across both forecast zones. This does not mean that you will see remnants of giant slides everywhere. Many were primarily in upper-elevation terrain above 7,500 feet, where terrain is prone to receive more wind,  is well-connected, and forms more obvious avalanche paths. However, many of the human-triggered avalanches as of late have been on small, steep, and treacherously-treed terrain-trap features. Where the slab thickness above the weak layer is around 2' seems to be the "sweet spot"—these are the areas where you are most likely to trigger a slide. Check for weak snow where you ride today—and remember that lack of evidence is not evidence of lack. 

Q: Are there areas where conditions are less dangerous?A: We have not heard reports of persistent slab avalanches, seen natural activity, or found much for unstable snow below ~7,000 feet. Both zones and the surrounding areas received a fair amount of rain during the last storm. The snowpack below this elevation exhibits a different slab/weak layer relationship than the snow above the rain line. The mountains around Big Creek [& the neighboring Warm Lake] have received a little less snowfall and more rainfall this season, and instability has generally been limited to wet slides or to areas where the wind has formed thicker drifts above the weak layer.

Q: Is it getting better?A: Yes. But the tougher question is by how much? With an especially pesky persistent weak layer like this one, there are no clear indicators of when the risk of triggering an avalanche has decreased to an acceptable level. Some important clues include decreasing signs of instability, such as a lack of human-triggering, a lack of failure in snowpit tests, and a prolonged period with no new loading from snowfall or wind. The consensus is that we're not there yet. Note that weak snow buried ~2 feet is deep enough that warm temperatures are changing the surface/slab above this weak snow, but not "strengthening" the weak layer itself. 

Q: What should I do about it?A: Glad you threw me an easy one. With no clear answer about how much the snowpack has stabilized, we need to offset the uncertainty with a healthy margin of safety in our terrain choices. In simple terms, this means continuing to choose conservative, lower-angled terrain that isn't threatened by steep slopes from above. And unfortunately for those who do not love crusts, the safest terrain lies where rain has fallen during the last storm and warm temperatures of recent days have melted and refrozen a larger portion of the snowpack. 

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