Avalanche Advisory for Saturday, 4-13-2013

This advisory expires at 12:00 midnight tonight.

Tuckerman and Huntington Ravines have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated pockets. Watch for unstable snow on isolated terrain features.

Well the snow that we were hoping for yesterday never really materialized. What we got instead was about 2/3 rds of an inch (2cm) of sleet, freezing rain and wet snow. Hourly data collection seems to have added up to more snow but due to settlement there is little in the way of dry, soft snow.   Probably the most important piece of data we see this morning isn’t the actual snowfall amount, it’s that the last few hours when precipitation was falling on the summit, it was recorded as freezing drizzle. So if there was truly snow mixed in with the other types, it’s locked in place by a frozen rain crust. All in all, skiing will seem like a survival training exercise due to the icy surface with little edge holding characteristics.  Climbing conditions should be pretty good for cramponing though approaches and lower angle routes like Escape Hatch and South Gully could be “punchy” unconsolidated, partially frozen crust. Steeper gullies will be firm enough to make steep sections less secure due to the limited boot penetration in the older, hard surface. Long sliding falls are the standout hazard type today with an ice axe, crampons and the ability to effectively employ belay methods being some of the keys to safe travel. Prepare for reduced visibility at times due to the unsettled weather with WNW winds in the 25-40 mph (40-65 kph) range with higher gusts to remind you that you are climbing on one of the windiest peaks in the world.

Springtime hazards worth mentioning include ice dams on the ice routes in Huntington, soft snow bridges over streambeds including the Little Headwall, and melting out  and thinly bridged moats around rocks and even some early crevasses in the Lip and Center Bowl.  A fairly significant glide crack (from the snowpack creeping downhill) opened up in the Lower Snowfields last week which is currently obscured but could swallow an unlucky ski or boot.

Our sincerest sympathies go out to the wife and child as well as the friends of Craig Patterson, an experienced avalanche forecaster for the Utah DOT, who was killed by an avalanche on Thursday while doing fieldwork in Big Cottonwood Canyon.

The Harvard Cabin is closed for the season; we are no longer issuing Huntington-specific forecasts at the cabin, but will continue posting this version of 5-scale advisories at the cabin.  The only camping permitting on the eastern side of Mount Washington is at Hermit Lake Shelters.

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
  • Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast.
  • For more information contact the Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or at Hermit Lake Shelters.
  • Posted 8:30 a.m., Saturday, April 13, 2013 . A new advisory will be issued tomorrow.

Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856

2013-04-13 Print friendly