This advisory expires at midnight.
Tuckerman Ravine has Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely in all forecast areas. Dangerous avalanche conditions exist.
Huntington Ravine has Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. Evaluate snow and terrain carefully to identify features of concern. Heightened avalanche conditions exist on specific terrain features.
AVALANCHE PROBLEM: Wind slabs are our primary avalanche concern today. 5” of new snow fell since yesterday afternoon and is currently being deposited in our terrain in the sheltered lee of WNW and NW winds. Hard but stubborn wind slabs will be created by the strong winds today. Expect these slabs to build quickly this morning when peak avalanche instability is likely to occur. Huntington Ravine, being higher and in a more windward location, may see more scouring than loading this morning. Some locations like Central, Pinnacle and Odell may also be sluffing heavily this morning.
WEATHER: Robins and crocus blooms are nowhere to be seen at Hermit Lake this morning. However, if you prefer wind drifted snow, rimed over conifers and biting arctic winds over the typical signs of spring, you won’t be disappointed. Wind speeds at the summit are gusting over 100 mph (160 km/h) this morning and are expected to hit 130 mph (210 km/h) later today. Steady 90-110 mph (145-175 km/h) northwesterly winds will make a journey above treeline a fool’s errand even though velocities will abate later to the 80-100 mph (130-160 km/h) range. The 5” (13 cm) of new snow from yesterday is still airborne, along with dense fog, reducing visibility to a few hundred feet at Hermit Lake. Temperatures will continue to fall as the cold front passes, ultimately bottoming out at -25F (-32C) sometime later today.
SNOWPACK: After the balmy but still winter-like conditions yesterday, the adventurous souls camping around Mount Washington are receiving a brutal wake-up call from weather concierge this morning. Tent flattening wind velocities and face numbing winds would push a quick journey to the nearest coffee shop to the top of my to-do list. Climbing and skiing conditions yesterday, and pretty good crowd of folks enjoyed the firm snow in both Ravines. Snow fall held off until around sundown and bumped new wind slab avalanches off the list of hazards to negotiate. Firm snow (pencil hard) dominated the scene with a few pockets of softer and harder snow here and there depending on aspect and the presence natural drift fences. Today’s wind event is creating similar conditions though I have no intention of venturing into avalanche terrain to verify this today. Expect peak instability sometime this morning, if it hasn’t peaked already, along with brutally challenging conditions for walking, much less for making careful snow stability assessments, group discussions on terrain selection and hazard mitigation.
- 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 8:25 a.m. Sunday, March 22, 2015. A new advisory will be issued tomorrow.
Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2713