Avalanche Advisory for Monday, 2-27-2012

This advisory expires at 12:00 midnight Monday, February 27, 2012

Tuckerman Ravine has MODERATE and Low avalanche danger. Right Gully, the Sluice, the Lip, the Center Bowl, and the Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. All other forecast areas have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

All forecast areas of Huntington Ravine have LOW avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

Remember this past weekend? Those were good times, eh? After all the fun, today certainly feels like a Monday morning. The excitement of a good snowstorm has passed, avalanche danger has subsided quite a bit, and the threat of clouds lowering is putting a gray feeling on the day. But if you’re a snow junkie, take comfort in the 1-3” (2.5-7.5cm) that are forecasted to fall later this afternoon and tonight. This snow is worth paying attention to, particularly if you’re going to be out on the mountain after dark, but I don’t think it will start early enough to affect stability today. Current conditions will remain for the daylight hours. Anticipate rising avalanche danger after snowfall begins to accumulate.

Yesterday, we were able to get into both ravines for a look at the aftermath of the weekend avalanche cycle. Huntington had slides in Pinnacle, Odell, and South. Much of the terrain in Huntington at this time is either old surface, bed surface, or wind-hammered snow, hence the Low rating. The strong winds that took place throughout much of the storm didn’t let a lot of snow stick to the gullies. The northern gullies have very little snow left in their upper sections.

In Tuckerman, slides were noted in Hillman’s, Duchess, Left Gully, Center Bowl, the Lip, and Right Gully. The one prominent location that appears to have not slid is the Sluice. Interestingly, the surface texture in much of the Sluice is almost identical to what you’ll see above the crown lines in the Bowl and Lip. I would treat this area with a healthy dose of caution. There are many bushes that were recently buried here, which often act as weak points in the slab. Judging from the thick debris in the floor from the Lip and considering that the runout is an enormous pile of boulders (i.e. Lunch Rocks), an avalanche in the Sluice would be a tough one to walk away from. The crown line(s) in the Lip and Center Bowl have reloaded to some extent. In these areas the Moderate rating is based on hangfire as well as the new loading on the old bed surface. In the aftermath of these avalanches, spatial variability takes on a whole new meaning. In Right Gully and the Chute, there is a mix of wind scouring and wind loaded areas. Climbers may find it easy enough to avoid the areas of greatest instability, but the lack of good snow in stable locations might cause a skier and snowboarder to gravitate toward the unstable snow. Finally, in Hillman’s, as well as the other areas rated at Low, expect isolated pockets of unstable snow. Hillman’s has a lot of old surface exposed, but also has numerous patches of newer slab on top of it. Left Gully was hammered by the winds and has good stability. And, the entrance into the Little Headwall is finally filling in with a reasonable amount of snow. There are still open water holes and some that were just recently covered, so use caution in this area. After this morning’s trip into Tuckerman I’ll try to post some pictures onto our website to show you what all this looks like.

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 the caretakers at Hermit Lake Shelters or the Harvard Cabin.  
  • Posted 8:55am. A new advisory will be issued tomorrow.

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

2012-02-27 Print Friendly