Expires at 12:00 midnight Monday 1-6-2014.
Tuckerman Ravine has Considerable and Low avalanche danger. Sluice, Lip, Center Bowl, Chute, Left Gully, and Hillman’s Highway have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. Lobster Claw, Right Gully, the Lower Snowfields, and the Little Headwall have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.
Huntington Ravine has Considerable and Moderate avalanche danger. Central, Pinnacle, and South gullies have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. All other forecast areas have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.
AVALANCHE PROBLEM: Wet avalanches are the primary avalanche problem today. Rain on snow and warm temperatures add weight and reduce strength of existing wind slabs and create the potential for spontaneous natural avalanches. On steeper areas of wind deposited snow from our previous storm cycle, the potential for this is greater. Humans out in the rain today could also be the trigger for these weak, rain soaked slabs. Additionally, be on the lookout for pockets of wind slab developing later in the day as rainfall changes over to snow. Last but not least, flowing water running onto or beneath slabs as a history of triggering larger slabs. These are infrequent but really hard to predict but are worth bearing in mind when route-finding on a micro-scale.
WEATHER: 1/2″ to an 1″ of rain and freezing rain will continue to fall this morning. Temperatures will drop midday and southerly winds will shift to the west. Light snow will fall on the heels of the departing low as the warm front moves out and a cold front moves in tonight. A trace to 2″ of new snow is predicted to fall during the afternoon hours and will blow into our forecast area on 55-75 mph westerly winds, possibly resulting in scattered pockets of wind slab later in the day. Temperatures will drop significantly through midday to around 10F from the 37F recorded at Hermit Lake this morning at 6:45am.
SNOWPACK: Successive low density snowfalls and strong winds have passed through this season resulting in a very discontinuous snowpack with variable conditions existing as you move from one snowfield to another. There are exceptions to this, such as Left Gully or Central Gully. These areas have long, continuous, and filled in snowfields especially compared to areas such as the Center Bowl or the Sluice. Northern gullies in Huntington have been scoured by the wind resulting in lean snow conditions. Fieldwork in Tuckerman yesterday revealed pencil hardness wind slabs of varying thickness but up to a meter thick in Center Bowl and below Sluice. This slab sat on 1F+ snow in one location. Areas rated Low today are far from being filled in enough to ski; any avalanche hazard here will be confined to very small isolated pockets.
- 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 0815 Monday, January 6, 2014. A new advisory will be issued tomorrow.
Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-285