Central Sierra Nevada

Problèmes avalancheux

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  1–2

  Partly cloudy skies and cold overnight temperatures will warm quickly this morning with strong April sunshine expected for today.  Crusts exist on most sun exposed slopes from partial sun exposure over the last couple days.  As these crusts melt away this morning, deeper areas of wet snow will form.  Areas around exposed rocks and cliffs bands, gully features, and lower elevation terrain, will warm faster than other surrounding areas.  The high April sun angle will allow wet snow to form on most all aspects as daytime warming occurs.  

  Melting surface crusts, roller balls, and pinwheels, will all be signs that the snow surface is warming and losing strength and that larger wet loose avalanches could become possible.  Even small wet loose avalanches can have increased consequences if taken into terrain traps such as rocks, trees, or over cliffs.  If the snow surface becomes deep, wet, or sticky, it's time to change aspects or move away from avalanche terrain.    

  

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpin
  • Limite forestière
  • Sous la limite forestière

  Probabilité

  Possible

  Taille

  1–1.5

  Northeast winds have increased in speed overnight into the moderate to strong range and are expected to continue through today.  Moderate to large amounts of recent storm snow is available for wind transport with blowing snow expected throughout the forecast region in exposed near and above treeline areas.  With the forecasted wind speeds for today, most wind slabs that form are expected to remain small in size.  Snow surface warming today may make any wind slab instability easier to trigger on sun exposed slopes.

  These new wind slabs will form just below ridges, near cornice features, and in gully features.  Look for blowing snow, new cornice formation, and newly forming wind pillows.  Identify where wind slabs are forming and move around any areas of concern.