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

  Blowing snow and shifting winds mean that slabs of wind drifted snow could exist on almost any wind-exposed aspect. Newer wind slabs will exist on slopes loaded by the NE winds. Older more difficult to trigger wind slabs may still linger on slopes loaded by SW winds. Some human-triggered wind slab avalanches large enough to bury injure or kill a person may remain possible today. Complex or extreme terrain including couloirs, cliffy areas, unsupported slopes, and steep convex rollovers will be the most suspect. Large cornices also still exist along the ridgelines.

  Cornices, blowing snow, drifted snow, firm hollow sounding snow, and other wind created surface textures can help identify where wind slabs may exist. These areas will also have more challenging snow conditions including scoured surfaces, sastrugi, and firm wind-packed snow. Seeking out more sheltered terrain will provide softer more consistent snow with fewer avalanche concerns.

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Possible

  Dimensione

  1

  Strong March sunshine and warmer daytime temperatures may cause enough warming for wet snow to form on sun-exposed slopes despite the cool NE winds. Loose wet instabilities like roller balls, pinwheels, and loose wet avalanches will be possible today. Some of these will remain small. Some of them could entrain enough snow to have consequences for backcountry travelers especially on long, steep, sun-exposed slopes or in areas where terrain traps increase the severity of an avalanche.

  Wet surface snow, small pinwheels, and roller balls can foreshadow larger loose wet avalanches. Expect wet sticky snow and variable sun crusts in addition to more loose wet avalanche concerns on sun-exposed slopes. Moving to more shaded and sheltered northerly aspects can help find colder soft snow and reduce exposure to avalanche concerns.