Bollettino valanghe

Central Sierra Nevada

Sierra Avalanche Center
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Pericolo valanghe

Wed
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Non aggiornato — questo bollettino è scaduto 4 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Warm weather and strong March sunshine will create wet snow that could slide down slopes today. Watch and feel for signs of unstable wet snow like wet surface snow, rollerballs, pinwheels, or recent avalanches. When you see clues like these, it’s time to move away from steep slopes that are capable of producing avalanches.

Problemi valanghivi

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Clear skies overnight should have allowed the snowpack to radiate enough heat out into the atmosphere for it to refreeze despite above freezing temperatures in many places last night. Strong sun and warm weather today will melt through this refreeze quickly creating a layer of wet snow on many slopes. Wet loose avalanches will be possible as the day warms up. Some of these could entrain enough snow to cause problems for backcountry travelers especially if they occur on long steep slopes or around terrain traps like gullies, cliffs, and creeks that magnify the consequences of these avalanches. Wet snow will be most prevalent on the E-SE-S-SW-W aspects, but some wet snow could also form on northerly aspects due to the high sun angles at this time of year. 

    Signs of potentially unstable wet snow include rollerballs, pinwheels, boot-top deep wet snow, or recent wet loose avalanches. Traveling on lower-angle terrain that is not below avalanche terrain or timing your travel to be off the snow before it gets too wet represent good strategies to avoid wet snow problems.

Avalanche Discussion

  • Observers reported some small skier-triggered wet snow sluffs around 11:30 am yesterday. Rollerballs and pinwheels also occurred yesterday on all aspects by noon. 
  • Snowmelt on SE-S-SW aspects has exposed bare ground in many areas limiting snow travel options on some of these aspects.
  • Melt-freeze crusts, previous wind scouring, and snowmelt should have limited the amount of blowing snow last night despite strong NE winds. 
  • The old facet layer that was buried on Feb 14 still exists on some NW-N-NE aspects. Data and observations indicate that it is gaining strength. 

Regioni coperte