Avalanche at Base of Pinnacle

On Thursday morning December 20th three climbers were suiting up after breakfast at the Harvard Cabin when USFS Snow Ranger Jeff Lane entered the building.  Jeff was in the process of writing the avalanche advisory for the gullies of Huntington Ravine and asking visitors what their plans were for the day.  Jeff got into a conversation with two of the three climbers about avalanche stability issues and the Considerable and Moderate postings for the Ravine.  Their plans were to climb for a couple of days with Pinnacle and Damnation as the desired routes, the former being the main goal.  With Pinnacle being posted at Considerable Jeff called Chris Joosen on the radio about his thoughts and concerns about a party ascending Pinnacle.  Jeff and Chris agreed that that they could not recommend Pinnacle posted at Considerable or Damnation Gully posted at Moderate, but would instead focus on presenting the stability facts.  Jeff discussed what gullies had more instabilities than others and convinced them Pinnacle was not a good idea.  Although Damnation held the possibility of unstable slabs, they were less likely and widespread than areas posted at Considerable.  After a 15 minute conversation they said they would climb Damnation today and perhaps hit Pinnacle tomorrow (Friday).  The weather conditions as they entered the Ravine included snow, light winds and limited visibility.  They decided to head up to Pinnacle to look at it and then traverse over to Damnation rather than head straight up to it.  After looking at Pinnacle from below they traversed under Central Gully and began heading across the top of the Fan.  They changed their plans partway across and headed back following their original plan to climb Pinnacle Gully.  On the approach to Pinnacle they began pushing through deep snow that they said was up to the chests.  They felt that because it was loose and unconsolidated that it was safe and not in risk of avalanching because in their opinion a slab did not exist. When the three were about 25 meters from the bottom of the ice which marks the traditional 1st pitch, the slope fractured and failed above them just below the ice.  At the time of slope failure the 1st climber was a few feet above the 2nd and about 10+ feet above the 3rd.  KA was out front and yelled “Avalanche!” and grabbed GW below him.  All three were flushed down the slope, but remained on the surface cart-wheeling with the entrained snow.  KA and GW were still next to one another about 75m below their high point while KB was sent almost twice that distance farther down slope.  They were extremely fortunate to have no injuries and to remain on top of the snow.  After shaking themselves off they proceeded to search for missing gear and decide what to do next.  Two wanted to climb the gully now that it had, in their opinion, been rendered safe by the release of its instabilities.  The third was done for the day.  They decided that they would all descend.

Lessons Learned: Often it is only in 20/20 hindsight that the reasons for an incident present themselves, but occasionally the natural world provides clues that were so obvious they should have been seen and heeded.  Each year we have examples of common mistakes that have human factors and psychology behind them even though the natural bulls-eye information was there.  This is such an incident.

Environmental Factors:

  • At 7am the summit temperature was around 15 F with a south wind at 20mph.  Approximately 3.5 inches of new snow was recorded at the summit while Hermit Lake in Tuckerman and the Harvard Cabin in Huntington each reported about 4 inches for the same period.  Snow continued through the morning bringing another 2-3 inches to all areas by noon.
  • Pinnacle is a steep E/ENE facing gully that is cross-loaded by S winds.  In addition to spindrift and sluffing from up high, the entire first pitch is water-ice which does not hold snow.  All of this snow piles up at the base of the gully on a slope of increasing angle averaging between 30-35 degrees.  This build up of snow accounts for the group’s comments of chest deep snow even though only 4-5” had fallen.  The light 7.7% density snow and light winds explains their impression that slabs did not exist.  Light density snow slabs can be practically indiscernible and although it appears unconsolidated and loose, even the slightest cohesion can create a slab.  Slab density closer to the ice was likely increased by the packing of spindrifts and sluffs from higher in the gully.
  • Pictures taken right after the slide by the group showed constant sluffing from the rock face that forms the gully’s left wall, further contributing to the accumulations on the slope.

Human Factors:

  • Jeff Lane spent 15 minutes of detailed conversation with the party about snow stability in Huntington and specifically the issues in Pinnacle.  The discussion ended with Jeff not being able to recommend their desired climb based on instability and the associated Considerable rating.  When traveling to various mountain ranges that have an avalanche advisory and you’re able to personally speak with the individuals that developed the forecast it should be acknowledged as key data.  In addition to avalanche forecasters there are ski patrollers, guides, Wardens, and Rangers working in their local mountains that can give you valuable safety advice worth listening to.  While you should not make your decisions based 100% on the advice of others, when available, use personal focused advice from experienced local avalanche expertise as a critical tool to help your decision making process.
  • The group initially passed Pinnacle and then convinced themselves that it was okay.  It becomes easy to overlook all the red flags when desire overcomes reason.  We must enjoy our winter pursuits on the mountain’s terms, not on our tight time schedule. It’s easy to make a go/no-go decision on the days that are truly nasty or sunny and stable.  It’s the large spectrum in between these two when you must err on the side of caution and fight the desire to “squeak through” and “beat” the mountain.  Snow stability is hardest to accurately assess when the margin of error can put you into either a green light or red light situation based on how you’re seeing the data.  The bulls-eye data can be a little more difficult to pick out.  For these reasons most fatalities occur under a Considerable avalanche rating.
  • Safe travel rules were not adhered to and rescue equipment was not worn.  Safe travel rules include (1) Travel one at a time, (2) Don’t travel over or under your partner, and (3) Have a plan in mind about exactly where you’ll go if an avalanche happens.  Number 3 can be very difficult to manage in every situation, but rules 1 and 2 mitigate risk well and limit the number of individuals in a potentially hazardous situation to one.  This is absolutely critical to individual and group survival if an avalanche does occur.  Having only one person buried allows more individuals to focus on the rescue, thus increasing the odds of survival.  On the other hand, having the whole group buried brings the group’s chance of survival pretty much down to zero.  This group was very lucky as all of them were caught, entrained in the debris, and brought downhill.  Had someone been buried, the big problem would have been the lack of beacons, probes, and shovels.  If anyone was completely buried this incident would have likely turned out tragically.