Avalanche Advisory for Saturday, March 31, 2018

Huntington and Tuckerman Ravine have LOW avalanche danger today. All forecast areas have Low avalanche danger. Generally safe avalanche conditions exist.

AVALANCHE PROBLEM: Due to the melt-freeze cycle the mountain experienced over the past 48 hours, avalanche concerns have subsided for the day. A big drop in temperature following ¾” of rain has locked the surface of the snowpack and left avalanche terrain with a smooth, icy surface. Long, sliding falls will be the main concern today for skiers and climbers and will necessitate the skillful use of crampons and ice axes. In addition to this, other spring hazards are starting to appear, though weather today should prevent further development of undermined snow and keep most rock and ice in place rather than cascading down.  Climbers should be wary of ice dams as the cold snap will have trapped running water under a coating of ice that is waiting for pressure release in the form of a tool or screw placement. The Little Headwall is now open water and not recommended as an exit for those looking to ski out of Tuckerman Ravine.

WEATHER: On Thursday morning, the summit of Mount Washington recorded above freezing temperatures that stayed above 32F for 30 hours. During this time period, the summit also recorded 0.75” of rain. At noon on Friday, temperatures began a downward trend that bottomed out at a current 3F on the summit and 14F at Hermit Lake. As today progresses, a ridge of high pressure over the region will keep skies clear until late in the day when upper level moisture will bring clouds in the evening. Temperature will be colder than it looks today with highs on the summit maybe reaching 20F by early afternoon. Wind is currently out of the NW at 65mph and will shift to the SW as high pressure moves out of the region late in the day. Wind speeds should drop to the 30-45mph midday and then increase again when the wind shifts to the SW.

SNOWPACK: As expected, our snowpack took a hit from yesterday’s rain. There is significantly less snow in the tops of gullies than earlier in the week. That being said, due to the porosity of the snow that arrived in early March, the snowpack was able to accept the rain well and we saw no drastic changes beyond the Little Headwall opening up. Today certainly has the appearance of spring, though those stepping out of their cars in the Pinkham parking lot at 7am might beg to differ. During our morning forecasters meeting, we discussed whether we thought the snow would soften today. Despite a combined give or take 45 years of experience, we struggled to say yes or no. If you are looking for spring skiing today, it might happen given the clear skies. That being said, cold temperatures and forecast wind speeds may prevent even south-facing slopes like Right Gully and Lobster Claw from softening. Wise skiers will carry crampons and an ice axe today and be prepared to down climb or wait and pray for the snow to soften.

The Sherburne still has full snow coverage from top to bottom, though ice is starting to appear in the usual places.

Tonight is the last night of operation for the Harvard Cabin, Starting tomorrow, the only place to camp in the Cutler River Drainage will be at Hermit Lake Shelters.

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 Harvard Cabin.
• Posted  8:00 a.m., Saturday, March 31, 2018. A new advisory will be issued tomorrow.

Helon Hoffer, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2858

2018-03-31

Avalanche Advisory for Friday, March, 30, 2018

Huntington and Tuckerman Ravines have MODERATE avalanche danger. All forecast areas have Moderate avalanche danger. Heightened avalanche conditions on specific terrain features.

AVALANCHE PROBLEM: Rain on cold, dry layers of snow raises our avalanche danger today. Warm temperatures and rain overnight will continue into the early afternoon hours today, adding strain to the weak layers that exist in the snowpack. There is a good chance that no natural avalanches will occur today, but any avalanche, natural or human-triggered, could be large and destructive. If, for some reason, you venture out into avalanche terrain in the cold rain today, keep this low probability but high consequence avalanche problem in mind. Temperatures will fall to the freezing level this afternoon and continue to drop through the night bringing improved stability to the snowpack. It will also create a hard, icy surface layer that sunshine and cool temperatures tomorrow may have a hard time breaking down.

Spring hazards are becoming prominent and should be considered in your terrain decisions. Long sliding falls on the hard, icy snow will be possible. Given the rain and refreeze, don’t count on the firm Styrofoam snow to be around tomorrow. Ice climbers should be aware of potential for ice dams in many climbs which can rupture with the placement of a tool, crampon, or screw. Above freezing temperatures will result in water flowing beneath ice which will become brittle in places when temperatures drop tonight. Undermined snow in stream beds will make exiting the Bowl challenging.

WEATHER: About a 0.4” (9.7mm) of rain fell overnight at Hermit Lake with more on the way today. The temperature is currently 39F on the summit and will slowly fall through the day, ultimately bottoming out at 8F on the summit at sunup tomorrow. West wind today will diminish a bit to 40-45 mph this afternoon but slowly ramp up and blow 65-70 mph tomorrow morning. Summit wind will diminish a bit tomorrow afternoon to 55-60 mph. Sunny skies are on tap and will likely seem appealing for a spring ski day but be prepared for borderline snow conditions which may struggle to soften even on sunny aspects.

SNOWPACK: Field time on the summit yesterday was a reminder of how important the direct sun and above freezing temperatures are to soften the snow surface. The more east facing snowfields were rock hard at 12 noon, despite sunlight filtered only by very thin, high clouds and temperatures at 34F. Wind from the west near 40 mph and indirect sunshine were enough to keep the snow from softening. Lower down the mountain, conditions improved on slopes facing directly into the sun but temperatures were quite warm there early on. Solar gain will be critical tomorrow. If you are choosing to come up on Saturday, remind yourself that the pressure that comes from a crowd of people is hard to withstand. Long-sliding falls often result in no injury whatsoever but have, on many occasions, resulted in life altering injuries and death. Look for sun softened snow, not the boot ladder with the most people.

Check our Instagram page, linked on our website, for conditions photos and additional updates. You don’t need an account to view our posts!

The Harvard Cabin will be open tonight and Saturday night and then close for the season.

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 Harvard Cabin.
• Posted  8:00 a.m., Friday, March 30, 2018. A new advisory will be issued tomorrow.

Frank Carus, Lead Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2858

2018-03-30

 

Avalanche Advisory for Thursday, March 29, 2018

Huntington and Tuckerman Ravine have LOW avalanche danger. All forecast areas have Low avalanche danger. Watch for unstable snow on isolated terrain features.

AVALANCHE PROBLEM: Temperatures will rise well above freezing today. So far, heating has been limited to the sunniest slopes and even then, wind and cool temperatures has limited heating to the surface. Today’s weather and snowpack trend is similar to the day a few years ago when a very large human triggered avalanche occurred on the summit cone. The warm temperatures that melt bonds between grains in the snowpack and create great skiing and riding conditions also melt bonds deeper in the snowpack. The first strong warming trend tests the strength of the snowpack, and in our case today, creates a low probability, high consequence avalanche problem. Natural and human-triggered avalanches are unlikely in most of our terrain but the threat of a large, hard slab makes it advisable to ski or ride a slope one at a time and to continue to carry your avalanche rescue gear. Large convexities or thin spots would be the most likely locations to trigger this type of avalanche. Wet loose avalanches could also occur in areas with strong solar gain or in the limited areas where soft snow remains. Low avalanche danger does not mean no avalanche danger!

WEATHER: A strong inversion this morning has valley locations slightly cooler than the summit which has already reached 30F. Tuesday night brought a trace amount of mixed precipitation to the mountain. Today looks clear and fairly calm though SW flow will bring clouds and eventually rain later this afternoon and evening. It looks as if these clouds won’t lower to become summit fog until nighttime though high clouds already developing this morning may reduce solar gain a bit this afternoon as they thicken. Temperatures should reach to the mid or high 30’s with 20-35 mph SW wind in the afternoon. Almost an inch of rain is forecast overnight and will further test our snowpack into tomorrow. Percolating rain in the snowpack will likely raise our avalanche concerns further tomorrow. 

SNOWPACK: The hard, icy melt-freeze crust that exists deep in the snowpack, beneath the firm wind slabs which developed March 17th, is one of the layers that will be a player in avalanche activity that occurs over the next couple of days. Rapid warming is one of the classic red flags signaling avalanche danger, along with heavy precipitation of any variety. The next 48 hours will bring changes to the snowpack which will ultimately reduce our avalanche concerns to the surface. Until then, we will continue to have the potential for a larger hard slab avalanche.

The Sherburne Ski Trail has good coverage top to bottom and should soften through the day. The usual scoured areas may start to reveal some rocks.

Check our Instagram page, linked on our website, for conditions photos and additional updates. You don’t need an account to view our posts!

The Harvard Cabin will be open all nights this week.

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 Harvard Cabin.
• Posted  7:45 a.m., Thursday, March 29, 2018. A new advisory will be issued tomorrow.

Frank Carus, Lead Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2858

2018-03-29

Avalanche Advisory for Wednesday, March 28, 2018

Huntington and Tuckerman Ravines have LOW avalanche danger. All forecast areas have Low avalanche danger. Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

 AVALANCHE PROBLEM: Snow on sun exposed slopes yesterday saw at least some degree of softening, which was followed by a quick refreeze in the afternoon. Areas seeing less direct sun continued to hold dry snow. Avalanche concerns are limited to small loose dry sluffs in this dry snow and loose wet sluffs when the refrozen snow warms again. The snowpack is exhibiting good stability and the current wintry mix of precipitation will not significantly change this. That said, we’re still far from a spring snowpack and it remains wise to travel one at a time in avalanche terrain while carrying a beacon, probe, and shovel.

 Spring hazards are becoming prominent and should be considered in your terrain decisions. Long sliding falls on the hard snow, which essentially all steep terrain holds, is a key concern today. If you brave the weather to travel in the alpine, crampons and an ice axe will be crucial equipment. Ice climbers should be aware of potential for ice dams in many climbs which can rupture with the placement of a tool, crampon, or screw. Recent above freezing temperatures has resulted in water flowing beneath ice and can create this hazard.

 WEATHER: A sunny and above freezing day yesterday gave way to increasing clouds which ultimately brought a wintry mix of precipitation to the mountain. Under an inch of mixed precipitation fell overnight and precipitation has tapered off this morning. Summit temperatures will hover around freezing as NW wind blows around 20 mph. Cloud cover should decrease to partly cloudy conditions by late today before increasing again by late tomorrow, bringing another round of precipitation that is currently forecast to fall as rain on the higher summits.

SNOWPACK: The nor’easters of two weeks ago ultimately built a firm upper snowpack which has exhibited good stability. Warming over the last two days did not penetrate deeply into this firm snow, though did allow softening yesterday to allow 4-6” of boot penetration on areas seeing greatest solar heating. These areas refroze quickly. Terrain which remained shaded or saw less direct sun continued to hold dry, cold, and firm snow. The mix of snow and sleet which fell overnight totaled less than a half inch at Hermit Lake. It has likely created additional variability in our snow surface but is not posing a stability concern. Avalanches are unlikely in the current conditions but the limited freeze-thaw action in recent weeks means that we still have a winter-like snowpack structure. The transition to an isothermal spring snowpack will likely occur in the coming weeks and is a time to begin planning for a variety of mountain hazards.

Check our Instagram page, linked on our website, for conditions photos and additional updates. You don’t need an account to view our posts!

The Harvard Cabin will be open all nights this week.

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 Harvard Cabin.
• Posted  8:00 a.m., Wednesday, March 27, 2018. A new advisory will be issued tomorrow.

Ryan Matz, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2858

2018-03-28

Avalanche Advisory for Tuesday, March 27, 2018

Huntington and Tuckerman Ravines have LOW avalanche danger. All forecast areas have Low avalanche danger. Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

 AVALANCHE PROBLEM: A significant warm-up today will make loose wet sluffs the primary avalanche problem on sun exposed aspects. Loose dry sluffs are still possible on steep and shady aspects. We expect these small avalanches which could easily knock you off your feet to occur primarily in the few inches of snow which fell late Saturday and into Sunday. The small and isolated pockets of soft and thicker wind slab which formed from that recent snow could begin to act as a wet slab on south facing slopes and should be on your radar in all terrain. The older, widespread, and hard wind slab that is thinly covered in many areas by the newer snow has been unreactive to human and natural triggers and this trend will likely continue. That said, a significant warming like our sun-exposed slopes will experience today can awaken previously unreactive layers at or near the surface. It’s again a reason that “Low” does not mean “No” avalanche danger, and that travelling one at a time, with your beacon, probe, and shovel, is advisable.

 Also be aware that while the sun will soften some aspects, others will remain hard, and sun softened snow can quickly refreeze with the return of shade. Crampons, ice axe, your ability to use them, and wise terrain choice are all necessary tools to prevent a high consequence long sliding fall. Sun will also warm ice today, making icefall a key overhead hazard to consider and manage.

 WEATHER: Current summit temperature is approaching 20F, already nearing yesterday’s high of 24F and forecast to exceed the freezing mark today. Yesterday’s high of 41F at Hermit Lake will almost certainly be exceeded. Yesterday was warm and spring-like, but today will be our first truly warm weather in several weeks. Southeasterly summit winds will remain under 20 mph until a warm front arriving late today brings slightly higher wind speeds and increasing cloud cover. Precipitation of a wintry mix is forecast to begin tonight but only fall in light amounts. Snow and sleet are forecast to total a trace to 2” by the end of tomorrow, with freezing rain or plain rain possible as well.

SNOWPACK: The few inches of snow which fell this weekend lies on a hard and stubborn two week old wind slab. This older snow also exists at the surface in many places. Today’s weather will be the first significant warming event on our current snowpack structure. Strong springtime solar energy and above freezing temperatures in the ravines will begin to transform our dry upper snowpack, though shady aspects may see minimal affects. Sun exposed aspects, which experienced some warming yesterday and a refreeze overnight, present the possibility for loose wet sluffs in the newer and softer snow today. The effect of warming on a previously unreactive hard slab, which is currently dominant in our upper snowpack, is notoriously tricky to forecast. We don’t expect avalanches from this layer, but it’s worth travelling as if one could occur. Skiers and snowboarders will likely find surface snow become more forgiving today on sunny aspects, though nearly all terrain holds snow allowing decent edge grip and excellent conditions for crampon travel.

The Harvard Cabin will be open all nights this week.

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 Harvard Cabin.
• Posted  7:50 a.m., Tuesday, March 26, 2018. A new advisory will be issued tomorrow.

Ryan Matz, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2858

2018-03-27

Avalanche Advisory for Monday, March 26, 2018

Huntington and Tuckerman Ravines have LOW avalanche danger. All forecast areas have Low avalanche danger. Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

 AVALANCHE PROBLEM: Limited wind transport of the several inches of snow which fell in the past 48 hours make loose dry sluffs our primary avalanche problem. Loose snow avalanches won’t bury you today but could knock you off your feet and are possible on most steep slopes. The new snow is distributed fairly evenly across our terrain, though a few areas saw wind scouring and the possibility for small, isolated pockets of wind slab does exist. A firm and generally smooth surface of older snow exists beneath the thin new snow. Conditions are generally edge-able and good for crampon and ice axe travel, but don’t expect to arrest a fall with any ease. A long sliding fall which could be caused by a loose dry sluff or just a stumble is likely your primary hazard to manage today.

 WEATHER: Skies have trended toward the current clear conditions as northerly wind has remained below 30 mph, with the exception of a few gusts. Currently, wind on the summit is NE at 20 mph with a temperature of 6F. High pressure is allowing this weather to hold through today and tonight, with temperatures warming by a few degrees and wind remaining mild by Mount Washington standards. These generally pleasant conditions should persist into tomorrow morning before clouds, rising temperatures, and increasing winds arrive with a warm front later in the day. Precipitation forecast to begin late tomorrow or early Wednesday is currently forecast to be a wintry mix.

SNOWPACK: The significant snow which fell nearly two weeks ago now was heavily wind transported. It ultimately became hard, dry, and stubborn to unreactive slabs which are widespread in our terrain. Three inches of snow has fallen since Saturday and has been relatively unaffected by wind, with the exception being isolated areas of scouring and even more isolated pockets of wind slab. It’s not quite dust on crust conditions, with the old hard snow providing decent turning conditions and great crampon purchase, but certainly consider sliding falls when choosing terrain today. Though it’s nearly April and spring-like weather may be coming later this week, expect winter snow on this crisp but blue sky day.

The Harvard Cabin will be open all nights this week.

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 Harvard Cabin.
• Posted  8:00 a.m., Monday, March 26, 2018. A new advisory will be issued tomorrow.

Ryan Matz, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2858

2018-03-26

Avalanche Advisory for Sunday, March 25, 2018

Huntington Ravine will have MODERATE and LOW avalanche danger today. Central Gully will have Moderate avalanche danger. Heightened avalanche conditions exist on specific terrain features; identify those of concern. All other forecast areas in Huntington have Low avalanche danger. Watch for unstable snow on isolated terrain features

Tuckerman Ravine will have MODERATE and LOW avalanche danger today. Sluice, Lip, and Center Bowl will have Moderate avalanche danger. All other forecast areas will have Low avalanche danger. Watch for unstable snow on isolated terrain features.

AVALANCHE PROBLEM: Snow that arrived overnight has the potential to form wind slab and dry-loose avalanches. Another shot of snow this morning will exacerbate this problem. While wind speeds should remain mild by our standards, the recorded snow has a very light density, making wind transport possible on low wind speed. Wind speeds should increase slightly this morning to above 40mph. This has the potential to load snow into the northern gullies in both ravines as well as cross-load Moderate rated terrain. With the combination of snow density and wind speeds, expect wind slab to be touchy to a human trigger, particularly with the firm bed surface it will reside on. While northern gullies in Huntington are more in the direct lee of today’s wind, a smaller fetch and confined, steep terrain will make dry-loose sluffing more of a an issue. If an avalanche occurs, it is likely to be small, but potentially enough to swipe your feet out from underneath you and lead to a long, sliding fall. As the bed surface in all avalanche terrain is firm, arresting a fall today will be difficult.

WEATHER: Afternoon and overnight snow showers capped off a largely bluebird day yesterday. As of this morning, the Summit recorded 1.1” of snow while Hermit Lake recorded 2.8” of 4% snow. Around dusk last night, wind speeds dropped to calm and shifted from the NW to the NE, before slowly increasing to a current speed of 35mph. Another inch of snow may arrive this morning while wind should shift to the N later in the day. Wind speed may increase slightly this morning before decreasing to the 20-35mph range for the afternoon.

SNOWPACK: March began with a bang in terms of snowfall and was followed by a period of 100mph wind. This left areas of firm wind slab with some areas seeing scouring. The firm wind slab has proven to be edgeable and unreactive to human or natural triggers. Areas of softer snow do exist in Huntington, but it still firm enough to make stopping a fall very difficult. Snow prior to yesterday afternoon will act widespread as a bed surface and should not contribute any volume of snow to an avalanche should one occur. New snow will likely cover variability in the old snow, hiding transitions in textures and possibly leading to mis-steps while skiing or climbing that could lead to a fall.

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 Harvard Cabin.
• Posted  8:00a.m., Sunday, March 25, 2018. A new advisory will be issued tomorrow.

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

2018-03-25

Avalanche Advisory for Saturday, March 24, 2018

Huntington and Tuckerman Ravine have LOW avalanche danger. All forecast areas have Low avalanche danger. Watch for unstable snow on isolated terrain features.

AVALANCHE PROBLEM: High temperatures in the low teen’s F, very firm snow surfaces and summit fog may have skiers dreaming about days of elevated avalanche danger today. Though climbers will appreciate the ease of climbing on the firm surface, skiers will be dealing with hard, fast conditions with no chance for softening snow. Light snow showers on light NW winds early this morning have created the illusion of fresh snow but don’t be fooled by the dust on crust effect. More snow showers today may create pockets of wind slab that will serve only to exacerbate the long sliding fall concern. For these reasons, expect low avalanche danger in all forecast areas due to new wind slabs this afternoon. Ice climbers should be aware that a climber fell up to their waist in the icy water behind an ice dam in Odell Gully yesterday. Expect the potential for an ice dam rupture to exist for a while on all ice climbs as spring continues and temperatures swing around the freezing point. Large chunks of ice are also beginning to appear on the floor of both Ravines.

WEATHER: Two inches of new snow may fall late this afternoon as a cold front pushes into the area today. Currently, the summit is in and out of the clouds at 10F with wind from the N at 11 mph. High clouds will thicken and lower through the day, bringing summit fog and challenging visibility, especially if snow showers develop later in the afternoon. All in all, today will play out like a mild winter day with the temperature struggling to reach above its current position. Relatively light NW winds should make travel above treeline more comfortable than usual.   

SNOWPACK: It’s been six days since any measureable precipitation fell on the summit besides the trace that fell overnight. Sixty-six inches of snow has fallen on the summit so far this month, accompanied by colder than normal temperatures, allowing our snowpack to bounce back a bit from the deficit we entered in January and February. There is currently 168cm of snow at the stake at the Hermit Lake snowplot, showing 5 cm of settlement since Thursday of what has remained a cold, dry snowpack at upper elevations. The 30” snowfall 10 days ago and 100mph+ westerly wind and avalanche cycle that followed, filled out most east and south facing slopes and runouts in an impressive way. For now, Ravines are in pretty good shape, though gullies on the right sides have top to bottom, but limited snow coverage. Snow surfaces most everywhere above treeline are very hard, but pockets of softer snow, some of it covered by a thick and grabby wind skin, exist in sheltered locations like the edges of gullies. This variability will keep you on your toes when skiing or climbing, especially considering the hard surface in most fall lines.

The Sherburne Ski Trail improved a lot after last week’s snowfall. Great coverage exists, though a bit of scouring may have exposed a rock or two in the usual wind hammered sections.

Be sure to check out our Instagram posts (@mwacenter) for up to date photos and videos. You don’t need an account to view them on your computer!

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 Harvard Cabin.
• Posted 7:50 a.m., Saturday, March 24, 2018. A new advisory will be issued tomorrow.

Frank Carus, Lead Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856

2018-03-24

Photo Update on March 23, 2018

 

Tuckerman Ravine. The hard wind slab is manageable on skis but ice axe and crampons are reassuring even on lower angle parts of the terrain.

The avalanche debris in lower snowfields and the bottom of Hillman’s is navigable and slowly filling in.

Huntington Ravine. The hard windslab is providing a excellent surface for cramponing. Ice fall is starting to show up in the bottom and will continue to be a problem as temperatures increase.

Pinnacle & Odell

Yale & Damnation

Multiple large chunks were observed in the floor this morning. Remember overhead hazards while making travel choices as the temperatures warm up.

 

Avalanche Advisory for Friday, March 23, 2018

 

Huntington and Tuckerman Ravine have LOW avalanche danger today. Generally safe avalanche conditions exist. Watch for unstable snow on isolated terrain features.

AVALANCHE PROBLEM: Wind slab is the avalanche problem today. It is unlikely that a human could trigger the current wind slab in our terrain due to its firm and supportive nature. As the slab itself has a high degree of tensile strength, an avalanche would be large, giving travelers in avalanche terrain a classic low probability, high consequence situation. Small areas of softer slab exist that are providing the isolated pockets of less stable snow. The surface of our snowpack is largely smooth, providing quality skiing, but also the ideal surface for a long, sliding fall. Losing a ski edge or catching a crampon point in steep terrain today will likely have dire consequences. With the possibility of 1” of snow today, dry loose sluffing in extreme terrain should be on your radar as wind speeds are forecast to be on the low side.

WEATHER: The fourth Nor’easter of March was less impressive than the others, bringing overcast skies and mild temperatures. We saw no new snow yesterday (or any of the previous four days), recorded a high temperature of 19F and a low of 9F on the Summit, and saw NE wind shift to the NW and stay in the 30-50mph range. Today will be somewhat similar, though summit fog should move in this afternoon. Wind will drift between N and NW and stay in the 25-40mph with periods of lower speeds. Up to an inch of snow may materialize today, though this should be hold off until later in the day if at all.

SNOWPACK: Significant snowfall in early-March followed by recent strong wind has left widespread, firm wind slab in most of avalanche terrain. This wind slab is supportive and is providing excellent climbing and good skiing provided you bring crampons and stay on your edges. Softer pockets of snow exist under terrain features and near the edges of gullies, particularly in the trees. Off trail travel that is not in a gully may require serious post-holing.

The Harvard Cabin is open this weekend.

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 Harvard Cabin.
• Posted 7:50 a.m., Friday, March 23, 2018. A new advisory will be issued tomorrow.

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

2018-03-23