San Francisco Peaks / Kachina Peaks Wilderness

Avalanche problems

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1–2

  Southwest winds will continue transporting new snow and building new wind slabs. Expect the likelihood of wind slab avalanches to increase throughout the day and become likely later in the day. Avoid wind-loaded, rounded, pillowed, rippled or corniced slopes, as these may have new sensitive wind slabs.

  Several wind slab-related avalanches were reported last week on steeper leeward slopes. Two of these avalanches were wind slabs on Rustler Peak. One was a natural, likely occurring on 3/15, which was 15' wide and about 12" thick running down the east face (see photo). The other was larger, and human triggered (on 3/16) from a skin track on the ridge. This crown was 150' wide and 6-24" thick, running 700' to the bottom on Humphreys Cirque.  

  

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1–2

  In the past few weeks, the snowpack near and above treeline has experienced a lot of change, developing sun crusts, a condensation crust, and undergoing drastic temperature shifts. These changes could create several weak layers that could facilitate propagation with additional snow on ice crusts and near surface facets; however, this problem has high uncertainty. Like the wind slab concern, expect the likelihood of this problem to rise as these weak layers are buried further by new snow. Although uncertainty regarding this problem is high, triggering a slide of this type could have severe repercussions. Backcountry travelers should continue to assess the snowpack for these issues. However, the best choice during this time of uncertainty is to make conservative decisions and avoid terrain with significant repercussions.