Flathead Range & Glacier NP

Avalanche problems

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1–2

  Southwest winds returned yesterday after a brief cold front brought northeast winds. Observers noted 4 to 6 inches of snow available for transport in upper elevations. This snow will continue to build into thicker slabs near ridgelines and cross-loaded features. Paying attention to changes in snow density will key you into places where wind slabs exist.

  The older generation of wind slabs appears stubborn; however, don’t be lulled into trusting older slabs. In steep terrain, avoid riding on pillows of dense, thicker snow. You can avoid the problem by choosing terrain where the snow is sheltered or scoured by the wind.

  

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Unlikely

  Size

  1–2

  Weak layers of buried surface hoar and facets exist 1 to 2 feet below the surface in the Flathead Range and southern Glacier National Park. You can avoid this problem entirely by sticking to slopes with lower slope angles. If you step out onto steeper slopes, avoid convex rollovers where you are more likely to trigger a slide. Even small avalanches have the potential to step down to buried weak layers. Choosing slopes with runouts free of trees and cliffs is a way to reduce your chances of trauma if the unexpected happens. Conservative terrain choices and a wide margin of error is the way to manage this problem.