Sawtooth & Western Smoky Mtns

Problemi valanghivi

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Likely

  Dimensione

  1–2

  Strong winds and consistent snowfall throughout the day will create fresh wind slabs in exposed terrain today. Shooting cracks are a clear sign you've found reactive wind slabs and should look for softer snow in more protected terrain. Look for smooth, rounded pillows, dunes or rippled surfaces and listen for hollow drum-like sounds under foot or machine. You're most likely to find these slabs of cohesive snow near ridgelines and in cross-loaded areas on the sides of gullies. Steering clear of these prominent wind features will significantly reduce your odds of triggering a slide.

  If the storm delivers more than 6 inches of snow by the end of the day, you may also find storm slabs in sheltered terrain. Shooting cracks and "upside down" or top-heavy feeling snow are indications that soft reactive slabs are forming. You can stack the odds in your favor by seeking out lower angle terrain and avoiding traveling above terrain traps such as trees, cliffs, or gullies at the bottom of steeper slopes.

  

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Unlikely

  Dimensione

  1.5–2.5

  While unlikely, we can't write off triggering large avalanches in middle and upper elevation terrain, especially during an active loading event. Unfortunately, you may not receive any obvious signs of instability before triggering one of these lingering monsters. We are most concerned with deeply buried weak facets found near the ground on middle and upper elevation slopes, especially those facing away from the sun.

  Triggering a slide on this layer is most likely on steep windy and/or rocky slopes where the snowpack depth is variable and in more sheltered terrain where the snowpack is around 3 feet deep. Small wind slab or storm slab avalanches  (Problem #1) may "step-down" into much larger persistent slab avalanches as they slide down slope.