A new General Bulletin will be issued if conditions warrant or within 72 hours of this release. General Bulletins are issued when isolated areas of unstable snow may exist within the forecast areas. Forecasts using the 5-scale danger rating system will begin when snowfields and bed surfaces become more developed. Please remember that avalanche activity may occur before the issuance of a 5-scale danger rating forecast. As always, make your own snow stability assessments when traveling in avalanche terrain.
Fast moving upper level low pressure “clipper systems” will dominate the prevailing weather conditions for the next few days providing a smorgasbord of conditions for mountain travelers to handle. Though the cold and wind challenges encountered on Mount Washington are well known, they have been slow to arrive this season. Warm temperatures and copious rain last weekend leveled our paltry snowpack which was composed or 20” of snow that had fallen so far this month. The rain and runoff beat up existing ice climbs and left a lean base for Tuesday’s and early Wednesday’s 8” snowstorm.
Our current weather pattern feels much more like a normal winter pattern though our snowpack is far from normal. The next few days will bring unsettled weather and enough moisture to drop a 2 or 3” of snow each day. This upslope snow will continue to grow existing small snowfields and create the potential for unstable albeit isolated, slabs. Wind speeds will be favorable for creating wind slabs as well, so use caution when approaching steep snow fields. Our terrain has a history of turning small scale snow events into a subtle, yet dangerous, avalanche problem that can catch the unwary off guard. Even a small avalanche can knock you off of your feet while the existing icy bed surface will make self-arrest challenging if not impossible on a steep slope.
The latest forecast has tempered, if not dashed, snow-lovers hopes for a major storm on Friday night and Saturday’s storm but it is likely that the mountain will receive some amount of precipitation. At this point, it seems as if it will be of a higher density frozen variety but it is still a little early for model run accuracy. Wind and reduced visibility will challenge summit bound climbers on Saturday so be sure to keep tabs on the storm track. We will more than likely put out another general bulletin on Saturday morning when we know more details about this weather maker. The cloud cap shrouding the Rockpile over the next few days will be changing the landscape and edging us closer to a winter snowpack which matches the winter weather.
- Safe travel in avalanche terrain requires training and experience. This bulletin 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. Bulletin posted at 10:00am, Thursday, January 14, 2016.
Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856