Avalanche Advisory for Tuckerman and Huntington Ravine

Posted 8:30, Saturday, January 8th, 2011

Tuckerman Ravine has LOW and MODERATE avalanche danger. The Lobster Claw, Right Gully, Left Gully, and Hillman’s Highway have Low avalanche danger.  Natural and human triggered avalanches are unlikely.  Watch for unstable snow in isolated terrain features.   The Sluice, Lip, Center Bowl, and the Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lower Snowfields and Little Headwall remain not posted due to a lack of snow in these areas.

Huntington Ravine has LOW avalanche danger. Natural and human triggered avalanches are unlikely. Watch for unstable snow on isolated terrain features. The Escape Hatch remains not posted due to a lack of snow in this area.

Over the past 48 hours snow stability has been slow to change, but some slight movement towards stronger snow has been occurring in areas that have been posted at Moderate in Tuckerman Ravine.  Mean while all areas in Huntington have been posted at Low over the past 2 days due to the scouring high winds that blew early in the week.  Little has changed in these areas with only about a half an inch (1.25cm) falling since the icy surfaces were exposed by 2-3 days of hurricane force wind velocities.  Expect continued hard surfaces in the vast majority of Huntington offering good cramponing for ascending.  Conversely, these surfaces will offer rapid decent of a dropped glove or you if you get tripped up.  Putting crampons on early and good self arrest skills are both crucial for a safe climb in Huntington or a summit trip if on steep snow.

The main stability problems continue to remain in the Lip and Sluice of Tuckerman due to them being in the direct lee of NW windloading that occurred several days ago.  The Center Bowl over to the Chute has been more wind affected offering a slight increase in stability comparatively, but still fall within the Moderate rating.  Right Gully and the Lobster Claw have dropped to Low due to some solar gain which increased slab temperatures just a bit more than easterly aspects, and some compaction from people.  Right gully has seen the most visitor use of all areas over the past 24 hours, albeit limited.  Some ski traffic occurred in the lower third of the gully which initiated a very small slab avalanche just below the narrows in the mouth of the gully.  This was quite small and innocuous, but does give us a little data about stability and the amount of variability that can be found out there right now.  Anticipate finding a high degree of spatial variability in areas posted at both Low and Moderate.  In areas posted at Low you will find hard old surfaces with some newer slabs that qualify as “isolated pockets”, particularly in those areas posted at Low in Tuckerman Ravine.  In areas posted at Moderate you may find stability one minute and weaker slabs the next, especially as you move into higher strong lee areas of the Sluice, Lip and their immediate outliers.

If the weather forecast become reality over the next 24-48 hours some upslope snow will be associated with a drop in temperatures, a counter clockwise shifting wind direction from the SE to the NW, and increasing velocities from very light to 80+mph (145kph).  The vast majority of these changes that will affect snow stability will occur tonight and tomorrow.  I would put money on the temperature and wind forecast, but will wait and see what happens for precipitation as upslope snow can be a bit hit or miss.  Expect anywhere from a trace to 5” (12.5cm) over the next 36 hours. So… stay tuned for our advisory Sunday and Monday morning for updates on how this develops.

The Tucks trail continues to ebb and flow between icy hell and not so bad.  Right now it’s nowhere near as bad as it’s been, but the majority of users have been wearing crampons or other traction devices with ski poles.  Much of the ice is covered by a dusting of snow so be thoughtful about foot placements particularly on the way down.  A few new ice flows have been slowly growing which may change the conditions again this week. The Sherburne ski trail is rugged, poor, bad, bare, icy, turf riddled, etc.  Enough said for most users but to spell it a little more clearly we need more snow to make a decent of this trail at all worth it.

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 the Harvard Cabin.
  • This advisory expires at midnight. A new advisory will be issued tomorrow.

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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravine

Posted 7:20a.m., Friday, January 07, 2011

Tuckerman Ravine has Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lower Snowfields and Little Headwall remain not posted due to a lack of snow in these areas.

Huntington Ravine has Low avalanche danger. Natural and human triggered avalanches are unlikely. Watch for unstable snow on isolated terrain features. The Escape Hatch remains not posted due to a lack of snow in this area.

If it was summer we’d probably not be complaining with our lack of precipitation, but complaint is all I can muster at this time of the year.  For the past 10 days the summit has received a total of 3.6” (9cm) of snow with a “trace” recording here and there.  So the streak continues with a rather slow start to the winter in terms of precipitation.  We are at 60% of our long term average from November through the first week of January corroborating what we are seeing as we look around, namely rock and ice where there should be snow.  HOWEVER, this doesn’t always tell the whole story.  How a storm comes in and what slopes get loaded can bring certain areas to normal or above, like some southern aspects such as Right Gully and the Lobster Claw.  As many avalanche start zones are still developing towards their average size others are already fully developed.  This is important to remember when new snow of any amount falls on our forecast areas.  Several inches from the north will affect avalanche potential in Right Gully and the similar south facing aspects much differently than the same snow from the south. The north facing start zones of Hillman’s Highway in Tuckerman and South Gully and the Escape Hatch in Huntington are much further behind with smaller bed surfaces for potential avalanches.  This all affects today’s situation as up to 2” (5cm) are expected from the SE and E.  I know 2” isn’t much, but at times it can have a meaningful impact on stability although today shouldn’t be one of them.  The SE wind will directly load limited snow on aspects that are still developing and have a number of early season anchors still in place.  Of course, other aspects have some cross loading potential but this should remain minor.  The caveat is that it’s an upslope energy driven snowfall which can surprise us from time to time so keep your eyes to the sky and ground and determine if we are exceeding the “up to 2 inches” forecast.

Tuckerman continues to harbor some instabilities from the last loading event on Tuesday and Wednesday that came in on W and NW winds. Human triggered avalanches are possible in steep terrain on strong lee slopes.  Areas from the Center Bowl to the Sluice would be the main areas of concern with their outliers, Right Gully and the Chute, following behind.  Huntington’s Low forecast is due to mostly hard old surfaces dominating the Ravine.  Expect to find some isolated areas of instability down low in the trees and in very protected areas under buttresses, boulders, and the like.  

Anyone venturing onto the mountain needs to be ready with good traction from the base of the mountain to the Summit. Long sliding falls are a real potential in these conditions; crampons and solid self arrest skills are critical for anyone venturing into angled terrain.   We have been alluding to the quality of the Sherburne Ski Trail as just being……well “bad” and today is no different. Even the most optimistic skier or snowboarder would have a difficult time calling it anything else. We’ll be posting a Weekend Update to our website this afternoon/evening, so if you’re planning a trip take a look for our latest thoughts on the upcoming 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 the Harvard Cabin.
  • This advisory expires at midnight. A new advisory will be issued tomorrow.

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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 8:10a.m., Thursday, January 06, 2011

Tuckerman Ravine has Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lower Snowfields and Little Headwall remain not posted due to a lack of snow in these areas.

Huntington Ravine has Low avalanche danger. Natural and human triggered avalanches are unlikely. Watch for unstable snow on isolated terrain features. The Escape Hatch remains not posted due to a lack of snow in this area.

Today is a great opportunity to practice being your own weather observer. Two key factors to watch for are 1) how much snow is falling and 2) how are the wind directions and speeds affecting the new snow. I know that may seem like a no-brainer to anyone who has even the slightest clue about snow stability, but today’s weather forecast is dynamic and variable. These two factors will play a prominent role today in just how far up the avalanche danger scale we go. Tuckerman Ravine starts the day with Moderate avalanche danger. This is due to the 3.5″ (9cm) of new light density snow that has fallen over the past few days, coupled with strong W and NW winds. Expect new windslabs to already exist in most areas of Tuckerman, sitting on top of a frozen hardpack left over from last week’s rain. Today’s wild card is the potential for upslope snow showers. The Observatory is forecasting a trace to 2″ of snow today, and the difference between the two ends of the range can make a big difference. If we meet or exceed the 2″ forecast, you should expect avalanche danger to be pushing the upper boundaries of the Moderate rating, which means you ought to be thinking about the possibility of natural avalanche activity. On the other hand, if we only get a trace, we’ll still have danger ratings sitting squarely in the Moderate range. Winds are forecasted to come down in speed and then shift directions late in the day. Loading may subside some as speeds decrease, but pick back up again as new snow falls or the directions shifts to the SW. Pay attention to what’s going on today and be flexible with your plan.

Yesterday’s strong winds have scoured much of the light density snow out of the gullies of Huntington. This is the primary reason why Huntington is rated at Low avalanche danger, even though the mountain has received over 3.5″ (9cm) of new snow. In isolated terrain features you should be watching for isolated pockets of unstable snow. The chances for this are greatest in the upper parts of the fan and down low in the gullies. As with Tuckerman, you’ll need to pay attention to how much snow falls today. If we meet or exceed the forecasted amounts expect increasing avalanche danger.

Anyone venturing onto the mountain needs to be ready with good traction from the base of the mountain to the Summit. Long sliding falls are a real potential in steep terrain and in places on the Tuckerman Ravine trail below Hermit Lake.  Crampons or similar gear are a must right now and solid self arrest skills are critical for anyone venturing into the steeps.   Despite a few inches of new snow, the Sherburne Ski Trail is in bad shape.  Even the most optimistic skier or snowboarder would have a difficult time calling it good.

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 the Harvard Cabin. 
  • This advisory expires at midnight. 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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 7:30, Wednesday, January 05, 2011

Tuckerman and Huntington Ravines have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanche are possible. The Escape Hatch, Lower Snowfields and Little Headwall remain not posted due to a lack of snow in these areas.

DON’T FALL ASLEEP OUT THERE! If you have been following our advisories you know that the majority of our existing snowpack is rock solid and digging a pit into this mass would require tools not typically found in a snow geek’s quiver (i.e., chainsaw).  It would be easy to glance over the subtle details of recent weather observations and ignore snow stability as a concern all together.  I urge you to pay attention to the details and venture out there with a well informed level of caution.  Over the past two days the summit has recorded 2.8” (7 cm) of light density new snow.  Hermit Lake picked up 2.6” (6.5 cm) of 5% snow since yesterday morning.  Winds have been primarily out of the W and are forecasted to be out of the NW today with speeds between 45 and 60 mph (72 to 96 kph) with higher gusts. The light snow accumulations paired with recent and forecasted wind speed and direction makes me think there is new wind slab out there clinging to an icy bed surface.  While the recent snow totals are lean, Mt. Washington’s wind does an outstanding job at putting it where it counts; into the Ravines. Upslope conditions are forecasted to bring scattered snow showers to the mountains today which grabs my attention even more.  In the past I have seen this type of forecast produce a trace of snow and I have seen it dump over a foot of light density powder.  Unfortunately, I don’t think conditions are right for the surprise foot of snow but you do need to pay close attention to how much is accumulating on the mountain today.  Expect increasing avalanche danger with each additional inch of snow because whatever falls will be transported into avalanche terrain and made into wind slab in lee areas. While all forecast areas have the potential to harbor new wind slab, I am particularly concerned about Tuckerman Ravine from Left Gully through Right Gully.  With the recent west winds grabbing snow deposited on Bigelow Lawn, a large flat area directly above and to the west of Tuckerman Ravine, I think these forecast areas will have more stability issues than others.

Snow won’t be the only thing trying to cling to an icy surface today.  Anyone venturing onto the mountain needs to be ready with good traction from the base of the mountain to the Summit. Long sliding falls are a real potential in steep terrain and in places on the Tuckerman Ravine trail below Hermit Lake.  Crampons or similar gear are a must right now and solid self arrest skills are critical for anyone venturing into the steeps.   I am sorry to report that the Sherburne Ski Trail is bad.  I don’t usually make such blunt statements about conditions because we all have our own opinions about how much fun ice and grass can be but it really is bad right now.  Water ice, frozen snow and long melted out sections and a dusting of snow to hide all of these surprises will greet any adventurer who wants to try.

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 the Harvard Cabin. 
  • This advisory expires at midnight. A new advisory will be issued tomorrow.

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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 7:53a.m., Tuesday, January 4, 2011 

Tuckerman and Huntington Ravines have Low avalanche danger. Natural and human triggered avalanches are unlikely. Watch for isolated pockets of unstable snow in areas with good protection from strong west winds.  The Escape Hatch, Lower Snowfields, and Little Headwall are not posted due to a general lack of snow in these areas.

Today will continue our run of bitterly cold days devoid of meaningful precipitation.  At least the ice is reforming quickly for those who are actually seeking it out.  Snow conditions on the other hand, leave something to be desired.  Scorching holiday temperatures melted much of our thin snowpack but by the time people were reading the Sunday paper the mercury was in freefall mode.  A 44F (25C) drop in temperature did a proper job of locking up meltwater and our world turned from slush to ice.  Down in the trees the snowpack was either consumed by the heat or left with a nasty crust that prohibits any recreational enjoyment. In open areas where the existing snowpack was more densely packed due to wind effect or previous avalanche activity, the snow surface has been converted to the bulletproof variety.  As a result LONG SLIDING FALLS are the main issue of concern today.  An ice ax is a critical piece of equipment if traveling in open angled terrain but it is useless if you don’t have the proper skills to go along with it.  Once you begin to slide you’ll pick up speed quicker than a jackrabbit out of the starting gate.  Instantaneous self arrest is your only help for waging a successful battle against gravity and the rocks and trees in your runout.

ICE DAMS are a significant concern for ice climbers especially in the confined gullies of Huntington.  A large volume of meltwater was coursing through the veins of the Ravine this past weekend and then the huge temperature drop shrunk those veins as rapid freezing took place.  In this scenario water effectively dams behind these constrictions waiting for a chance to release pressure.  Be gentle, avoid swinging into convexities, protect often with rock gear when possible, and station belays in protected areas. Today’s weather forecast calls for another day of temperatures climbing back to the single digits above zero F and winds slowly diminishing from their currently sustained speeds greater than 70mph (113kph). Expect arctic conditions above treeline.

We usually don’t go into great detail about trail conditions on the mountain but today it’s worth it because they’re downright nasty.  I didn’t run into too many people on the trail yesterday but everyone I saw was wearing crampons or microspikes.  There is so much water ice on the Tucks Trail that you cannot make it up the trail without this type of equipment unless you venture into the woods and cause unnecessary resource damage.  Additionally there are places where a sliding fall would send you a few hundred feet down a rock-studded iceflow.  Situational awareness will help you make good decisions that on any other day would have been trivial.  We’ve personally seen a number of failures with lightweight traction devices recently so keep an eye on your equipment in these challenging conditions.

The Sherburne Ski Trail lost much of its snow and there are LONG sections that have nothing but grass and water ice.  There are also rocks, brush, and open waterbars. And where snow exists, it’s very hard and choppy. I checked out a long section yesterday and wouldn’t recommend it to my worst enemy.  Until things change pack your mouthguard and plan extra time for your descent or walk the hiking trail down to Pinkham.  We need snow!!!

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 the Harvard Cabin.
  • This advisory expires at midnight. A new advisory will be issued tomorrow.

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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 8:00a.m., Monday January 3, 2011

Tuckerman and Huntington Ravines have Low avalanche danger. Natural and human triggered avalanches are unlikely. The Escape Hatch, Lower Snowfields, and Little Headwall are not posted due to a general lack of snow in these areas.

The past few days have been interesting at least. Conditions on Mt. Washington have been changing rapidly. About one week ago we got a great snowstorm that snapped us out of our post-holiday languor. For a couple days people were enjoying powder runs on the ski trails and there were some impressive avalanches in the ravines, but then we had temperatures shoot above 40F all the way to the summit on Saturday night. Right before our eyes, all that new snow began to melt away. Warm weather persisted until yesterday, when summit temperatures began to fall. As of this morning they’ve fallen by 40 degrees F since their peak. As for avalanches, conditions are very stable thanks to all the wet snow freezing into a solid mass of ice. It will remain this way until we get either some new snow or a significant change in weather. There are some light snowfalls expected through the week in the mountains. These won’t be much, but they may affect stability ratings, so check the advisory daily if you’re planning a trip to avalanche terrain.

The drop in temperatures will also bring out some of the other winter hazards that have been in hibernation through the off-season. First on my list of things that can hurt is a LONG SLIDING FALL. If you’re heading into steep terrain, know that it will be difficult to arrest your fall on the icy surface. The lack of snow increases your chances of hitting rocks and trees in a fall. Have an ice axe and crampons with you, know how to use them, and practice before you get into terrain where a fall carries high consequences. GENERALLY TREACHEROUS TRAIL CONDITIONS makes the list as well. Traction footwear and a set of ski poles can go a long way toward keeping you on your feet in low-angle terrain. Also of concern are ICE DAMS that are forming as newly formed ice plugs up the drainage channels behind ice climbs. If you pass through these challenges and make it to treeline, you’ll find ARCTIC CONDITIONS AND VERY STRONG WINDS gusting over 80mph today. All in all, with the recent dynamic conditions and current weather you should be on your toes today regardless of where you travel in the mountains.

I also feel compelled to describe the current sad state of the John Sherburne Ski Trail. Much of the trail has sections melted down to bare grass. Where it’s not grass there is a lot of water ice. There are also rocks, brush, and open water. And where snow exists, it is very hard and choppy. Until things change plan a little extra time for your descent or plan to walk the hiking trail down to Pinkham.

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 the Harvard Cabin.
  • This advisory expires at midnight. 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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 8:25a.m., Sunday, January 2, 2011

Tuckerman and Huntington Ravines will have Low avalanche danger today.  Natural and human triggered avalanches are unlikely except for isolated pockets in steep terrain.

We are seeing the light at the end of the tunnel as our December/January thaw rapidly comes to end over the next 12-24 hours.  Before the warm air mass exits however it will give our snow pack one last punch and stranglehold today eating it up a little more before the cold air nudges it out of the region.  Temperatures in the Ravines and their associated avalanche start zones have been in the 40-45F (4-7C) range quite a bit over the past couple of days and currently hover there waiting for some air mixing and increased winds later today.  The slow increase in air temperatures on Thursday and Friday allowed our snowpack to adjust to these warm changes never pushing it over the edge to avalanche.  We believe we reached peak instability yesterday and overnight before falling down the danger rating scale during the early morning darkness.  We transitioned from Considerable to a Low forecast today because we believe the natural avalanche potential moved from being possible to unlikely.  The decline in the avalanche potential of wet slabs will be a gradual process during the first part of the day as temperature moves from 45F (7C) towards freezing but melt water percolation and some additional light rain continue.  When the mercury drops below 32F (0C) and the wet snowpack begins to freeze from the surface down the avalanche potential will plummet late in the day.  This occurs due to a rapid increase in tensile strength with the development of our lovely New England boilerplate.  Until this occurs we still have a minor concern about pockets that may have lubricated bed surfaces and are isolated and confined by surrounding terrain features.  An example would be wet slabs overlying blue water ice in the Center Tuckerman Bowl and gullies in Huntington.  Although we do believe avalanche activity is unlikely, snowpack stability does not usually make Hopscotch jumps from one danger rating to another instantly, it is a transitional process.  So as of right now we have flowed from “possible” to “unlikely” and will continue declining until the cold air locks up all areas during the overnight. 

The return of winter will be accompanied by the development of very hard snow surfaces and bountiful water ice.  Expect all angled terrain to be very slick and hard making crampons and ice axes imperative along with the experience to use them.  A sliding backpack down one of the Ravines would likely break the sound barrier tomorrow as temperatures hit 0F (-18C) tonight on the higher summits turning slopes into inclined hockey rinks without the boards.  Ice climbers should also be prepared for ice dam development as water channels under the existing ice become blocked, backing up water and increasing the pressure.  This phenomenon can have impressive and powerful results when discharged by a crampon kick or tool placement.   

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 the Harvard Cabin.
  • This advisory expires at midnight. A new advisory will be issued tomorrow.

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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 8:45a.m., Saturday, January 01, 2011

Tuckerman Ravine: The Lip, Sluice, Right Gully, and Lobster Claw have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. The Center Bowl, Chute, Left Gully, and Hillman’s Highway have Low avalanche danger. Natural and human triggered avalanches are unlikely. The Lower Snowfields and Little Headwall are not posted due to a general lack of snow in these areas.

Huntington Ravine: All forecast areas have Low avalanche danger. Natural and human triggered avalanches are unlikely. The Escape Hatch is not posted due to a general lack of snow in this area.

If you think you’re head is a little foggy from last night’s revelry, you should try to see through the soup hovering in the ravines this morning. This surely is an interesting and rather unwelcome start to the New Year. Temperatures at Hermit Lake are currently a balmy 42F (5C) which is causing our already thin snowpack to grow thinner by the hour. Throughout the day, temperatures will remain well above freezing in the ravines. Light rain may fall during the daylight hours and is likely after take place after dark. All this adds up to quite a bit of free water in the snowpack, and this water is what gives us concerns about snowpack stability on the northern side of Tuckerman. Prior to the melting, new snow had been deposited into S and SE aspects of Tuckerman Ravine (i.e. the same areas that are rated Considerable today). These areas had seen some settlement, but as they become saturated with liquid from prolonged melting and rain, the chances for avalanche activity in this new snow layer will increase. Today’s Considerable rating is based on this possibility of natural avalanche activity. The interesting part is that as avalanche danger increases today, the most appropriate rating jumps right from Low to Considerable. There will be a critical moment when the potential for natural avalanches shifts from “unlikely” to “possible.” Don’t expect your snowpits to give you much reliable data about when this will happen. Wet snow avalanches can be difficult to predict, even for professionals. Thankfully New England frequently offers us chances to witness this phenomenon, and our collective experience here tells us it’s a good day to be cautious.

Elsewhere in Tuckerman and throughout Huntington the new snow was scoured down by strong winds. Since the slabs that concern us in the northern side of Tuckerman are either very small or altogether absent, Low avalanche danger is today’s rating here. However, warm temperatures like today are not necessarily a day at the beach. You should still be mindful of hazards such as the potential for falling ice and rock, ice screw placements that melt out rapidly, etc. If you’re heading out for an extended trip, expect temperatures to rapidly fall through the day tomorrow. Summit temperatures look like they’ll drop about 40 degrees F over a 24-36 hour period!

Finally, the John Sherburne Ski Trail will be hit hard by this warm spell. Already some sections are melting out; you should expect rocks, open water, brush, and bare spots.

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 the Harvard Cabin.
  • This advisory expires at midnight. 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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 7:55a.m., Friday, December 31, 2010

All forecast areas of Tuckerman and Huntington Ravines have Low avalanche danger today. Natural and human triggered avalanches are unlikely. Watch for isolated pockets of unstable snow in steep terrain. The Little Headwall, Lower Snowfields, and Escape Hatch remain “not posted” due to a general lack of snow in these areas.

Happy New Year’s Eve, everybody. What could possibly be a better way to end the year than with a strong surge of warm air from the south that will push summit temperatures well above freezing for a couple days? If nothing else, this is an ending that fairly represents the weather patterns of 2010—a bit of a roller coaster ride at times and always leaving us wanting more cold and snow. We got out yesterday into both ravines and found good stability in much of the terrain. Huntington was scoured down to a solid Low rating, as was much of Tuckerman Ravine. In the Center Bowl, Chute, and Left Gully the snow had been hammered by strong winds into a Styrofoam-like consistency. On the northern side of Tuckerman the story is a little different. This side was in the protected lee of the strong winds, which allowed for a little more deposition of new snow into isolated pockets that may still harbor instabilities. Also, temperatures, sun, and wind yesterday were just enough to keep surface snow cold in all but the most sheltered and sunny aspects, which hindered the stabilization of many of these areas. To further complicate things, at this point of the season we still don’t have full-winter snow coverage, so there is a lot of spatial variability in the bed surfaces, weak layers, and anchoring out there. Although there is a complex dance going on between all the different variables, the point is that we fit within the definition of a Low danger rating for all forecast areas. However, there are potentially unstable pockets to watch out for, so please don’t be lulled into the numerous human factors that can blind your decision making skills.

The warming that has already begun will continue today through tomorrow, with a little bit of rain thrown into the mix for New Years Day. This warming does have the potential to affect the snowpack, so we want it to be on your minds over the next two days. Warmth, whether from direct sun, rainfall, or general warmth, can cause slabs to lose strength as bonds between snow grains are broken down and water percolates into the snowpack. This loss of strength can correlate to an increase in avalanche danger. With such a strong degree of spatial variability around the ravine, we can’t rule out the potential for avalanches completely. Remember that Low danger means avalanches are unlikely, not impossible. Expect this to be more of a factor tomorrow than today, so if you’re making plans for Saturday, be sure to read the morning advisory. We’ll also be writing out first Weekend Update of the season this afternoon/evening, so check our website tonight as part of your planning process.

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 the Harvard Cabin.
  • This advisory expires at midnight. 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

Printable Advisory

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 8:40.m., Thursday, December 30, 2010

Tuckerman Ravine: The Lobster Claw, Right Gully, Sluice, Lip, Center Headwall and Chute have MODERATE avalanche danger.  Natural avalanches are unlikely and human triggered avalanches are possible.  Left Gully and Hillman’s Highway have LOW avalanche Danger.  Natural and human triggered avalanches are unlikely except for isolated pockets in steep terrain. The Lower Snowfields and Little Headwall are not posted due to a lack of snow in these areas.

Huntington Ravine: All forecast areas have LOW avalanche danger.  Natural and human triggered avalanches are unlikely except for isolated pockets in steep terrain.  The Escape Hatch is not posted due to a lack of snow in this forecast area.

It’s finally a beautiful clear day on the mountain.  Brian and I were antsy to get in the field and assess conditions yesterday but the weather did not cooperate as fog and blowing snow dominated the day.  Today, Jeff and I will get out in the snow and determine if our initial impressions are correct.   Currently, Tuckerman has a fair amount of wind affect and my gut tells me “it’s hard and stable”, but my mind says “you’ve been fooled before, always remember history”.  Because of this a few areas such as the Chute and the Center Bowl had me sitting on the Low-Moderate fence and decided I needed to get my hands in it before falling to the Low side. 

The other factor for me is the warm weather taking hold of the hills with a reading of 34F (1C) at Hermit Lake as of 8:15 making temperature the main issue for the day. This warming trend also kept me at the Moderate rating level particularly those in the direct sun.  Slopes and gullies with a S or SE aspect such as the Lip, Sluice, and Right gully should be the most suspect due to our the most recent loading coupled with the current warming.  The solar gain of December will take some time to work into cold dry slabs, but the warm air in the region will have a greater effect slowly penetrating through the day.  I do not believe as of now, with the temperatures forecasted, that the impact will be quick enough to cause significant stability issues.   Although it will begin to be cause for some concern later today if temperatures push beyond the forecast.  Some wind protected slopes facing the south may start to get fairly warm at peak height of the December sun.  We will be watching this closely today and with this warm trend continuing tomorrow we will likely focus most of the discussion on it in Friday’s advisory.  Stay tuned. 

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 the Harvard Cabin.
  • This advisory expires at midnight. A new advisory will be issued tomorrow.

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

Printer Friendly Avalanche Advisory PDF