Bollettino valanghe

Central Sierra Nevada

Sierra Avalanche Center
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Pericolo valanghe

Alta quota
1 · Debole
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
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Non aggiornato — questo bollettino è scaduto 12 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Avalanche danger remains LOW for all elevations and aspects. Isolated areas of minor instability are unlikely but not impossible. Normal caution is advised.

Problemi valanghivi

  • Cornices

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    1

    Avalanche concerns for today remain minimal. Small shallow isolated wind slabs are unlikely but not impossible in near and above treeline areas. Some redistribution of snow on the ground is possible today with the switch from NE to W winds. The greatest threat from triggering an isolated wind slab is secondary terrain hazards such as rocks, trees, and cliffs that one could be pushed into or over rather than the size of the avalanche itself.

    Areas of surface wet snow will form today in response to daytime warming. Any areas of associated surface wet snow instability are expected to remain small and inconsequential in the form of human triggered roller balls, pinwheels, and small loose wet sluffs.

    Snowpack stability across the forecast area is good but not perfect. Exercise normal caution and employ best practice travel techniques while traveling in and around avalanche terrain.

Avalanche Discussion

Observations made yesterday on Castle Peak (Donner Summit area) found small shallow wind slabs 2 to 4 inches deep on NW aspects in near treeline terrain at 8,500'. Very minimal amounts of wind transport were observed with slab creation having previously occurred under similar NE winds on January 28. The slab/weak layer combination showed no evidence of instability in the areas traveled with skier triggered cracking highly localized and without propagation. Areas of full shade all day had resisted snow surface melt with areas of shallow unconsolidated recent storm snow lingering. Sun exposed areas were in full melt-freeze regime. Wet surface snow 1 to 2 inches deep was observed on SE-S aspects at 12:15 pm. Convective cooling from NE winds slowed snow surface melt during the mid morning hours. By early afternoon, snow surface melt was occurring in nearly all sun exposed areas on SE-S-SW aspects.

Observations received yesterday from Relay Peak (Mount Rose area) showed no further evidence of instability associated with the crust/rounding facet combo that exists in the upper snowpack in many locations around the forecast area. This relative weak snow below strong crust is most pronounced in the Mount Rose region, but has been observed to varying degrees around the rest of the forecast area. It remains worth keeping an eye on , but is not a current instability concern.

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