Avalanche Advisory for Monday, March 3, 2014

This advisory expires tonight at 12:00 midnight.

Tuckerman Ravine has MODERATE and LOW avalanche danger. The Sluice, Lip, Center Bowl, Chute, Left Gully, and Hillman’s Highway have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lobster Claw, Right Gully, Lower Snowfields, and Little Headwall have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. 

Huntington Ravine has MODERATE and LOW avalanche danger. Central, Pinnacle, Odell, South, and Escape Hatch have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. North, Damnation, and Yale gullies have Low avalanche danger. Natural and human triggered avalanches are unlikely. However, watch for unstable snow in isolated terrain features in these areas. 

AVALANCHE PROBLEM: Wind slab is the primary avalanche problem today. The largest and most concerning of these recently formed slabs can be found in Tuckerman’s Sluice, Lip, Center Bowl, and Chute, as well as in Central Gully in Huntington. Other areas of Huntington have less continuous problem areas, but certainly there are locations within each of the gullies that you’ll need to treat with respect. In Tuckerman, the different forecast areas today are doing their best to stretch the range of Moderate. Areas such as Hillman’s and Left Gully are on the lower end, having been more wind effected, while locations in the general headwall area are pushing the upper limits of Moderate. In addition to the upper wind slab layers, we are also beginning to think about persistent slabs being an avalanche problem. This problem is related to the old freezing rain crust that is breaking down over time. Faceted snow near this layer can act as a weak layer for snow above it, and the weakened crust offers less protection to any underlying slabs than it previously had.

WEATHER: We’re in a period of cold dry weather for the next several days. Sadly, no big storms are on the horizon. Today’s weather will be standard winter weather on Mt. Washington. Winds will blow around 45-60mph with temperatures on the summits well below zero F. Yesterday we received 0.7” (1.8cm) of new snow and winds blew from the WNW around 40-50mph (65-80kph) much of the day.

 SNOWPACK:  To be honest, I found the snowpack yesterday to be a little on the boring side. There wasn’t enough stability to make me feel confident enough to want to ride some of the nice looking lines that are filling in, but the instability in my location wasn’t so great that my nerves were tingling. The small amount of new snow was blanketing most every surface in a soft unconsolidated layer, but it was only a couple inches deep at most. Below the new snow is a mostly “right-side-up” snowpack of 1F+ over P, sitting on top of a deteriorating and faceting crust. The interface between the 1F and P slabs is where I’d put my money on a person initiating an avalanche. From there I’d double down that it would rip out down to and including the crust. Some of the more wind-exposed locations have crust on the surface (good stability here) or more recent slabs that are heavily wind effected (fair-good stability in these).

It is great to see some of the classic ski lines finally coming into shape. The upper Chute, the Center Bowl, and the Sluice have all recently gone from “where’s the snow” to “that looks good…” The challenging thing is knowing when these lines will be stable enough that the risk involved falls into the manageable category. With the weather I see on the horizon, these routes will not easily move to a clear Low danger. So until then, they will sit there tempting skiers and riders. My advice to you, as always, is to do your own assessments and make your own decisions. Don’t fall into the trap of believing that tracks on a slope imply safety. Don’t talk yourself into why you know better and why it won’t happen to you. The slopes will eventually stabilize, you might just need to wait a little while longer if you want to keep the risk down.

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 Visitor Center, or the caretakers at Hermit Lake Shelters and Harvard Cabin.
  • Posted 8:35a.m. 03-03-2014. 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

2014-03-03 Print Friendly