Central Sierra Nevada

Problemi valanghivi

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Possible

  Dimensione

  1–2

  Winds yesterday exceeded forecasted amounts with blowing snow and wind slab avalanches reported.  These winds were variable anywhere from the NE to the S and reached speeds of 20 to 30mph with gusts over 40mph.  Winds have decreased overnight and are expected to remain light today before shifting to the SW this afternoon.  Wind slabs may remain reactive today in wind exposed upper elevation terrain.  These wind slabs formed easily with the low density recent storm snow with reported avalanches running full path.

  These wind slabs may have formed in unusual locations from the recent variable winds and changing directions.  Many gully and terrain features could be cross loaded.  Look for signs of previous or current wind transport.  Blowing snow, new cornice formation, and snow surface scouring will be clues to where these wind slabs may have formed.  Move carefully around these areas of concern.

  

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Possible

  Dimensione

  1–2

  Wet snow instabilities have been limited over the last couple days with increased cloud cover and winds.  Warmer temperatures are expected today with decreased winds and strong sunshine.  Wet loose avalanches will become possible as daytime warming occurs at all elevations.  Most wet snow instabilities are expected to be smaller roller balls and pinwheels, but larger wet loose avalanches could happen as additional warming occurs today.

  Roller balls and pinwheels could indicate that the surface snow is losing strength and that larger wet loose avalanches could become possible.  If the surface snow becomes wet and deep, it's time to change aspects or move to lower angle terrain.  Terrain traps could easily magnify the consequences of being caught in even a small wet loose avalanche.