Bollettino valanghe

Central Sierra Nevada

Sierra Avalanche Center
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Pericolo valanghe

Sun
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
3 · Marcato
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In sintesi

We are now at four nights in a row of poor refreeze conditions with record to near record warmth each day. Unstable areas of wet snow are expected again today. Consider avoiding travel in or below avalanche terrain in areas where wet snow is more than a few inches deep, especially if it feels unsupportable.

Problemi valanghivi

  • Loose Wet

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

    SW winds have mixed out any air temperature inversion and it is just plain warm out there this morning. 54 of the 58 weather stations reporting air temperatures between 6,175' and 9,650' were above freezing at 5 am this morning. Periods of cloud cover last night will have further contributed to very poor snow surface refreeze conditions. Any weak snow surface refreeze that managed to occur last night will not last long in sun exposed areas this morning. Cumulative amounts of deep wet snow have formed over the past few days that have not refrozen overnight. You could encounter deep and potentially unstable wet snow conditions just a couple of hours after sunrise today.

    Conditions are ripe for a wet loose avalanche if you can sink into wet snow near to beyond the top of your boot or if the wet snow is feeling unsupportable while traveling on your equipment. Consider avoiding all travel in or below avalanche terrain when these conditions exist. Don't be fooled by seemingly supportable snow surface conditions in areas of previous compaction such as high traffic areas near trailheads or on snowcovered roads.

Avalanche Discussion

  • Deep, wet, and unsupportable snow has been encountered by 9 to 10 am the past three mornings, especially on N-NE-E aspects.
  • An isolated wet slab avalanche remains in the back of our minds right now. In some locations, meltwater has reached the old facet layer that was buried on Feb 14 and remained weak in very isolated areas on some shaded NW-N-NE aspects. Snowpit data from Thursday indicates that an isolated wet slab avalanche is not outside the realm of possibility at this time.
  • Snowmelt has intensified on all aspects and elevations throughout the forecast region.  Most SE-S-SW aspects have exposed bare ground in many areas limiting over snow travel options on these aspects.

Regioni coperte