Avalanche Advisory for Tuckerman and Huntington Ravines

Posted  8:40a.m., Friday, January 21, 2011

Tuckerman Ravine has HIGH avalanche danger today. Natural avalanches are likely and human triggered avalanches are very likely. Travel in avalanche terrain is not recommended. There are only two exceptions to this rating. The Lower Snowfields have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. The Little Headwall has Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.

All forecast areas of Huntington Ravine have HIGH avalanche danger. Natural avalanches are likely and human triggered avalanches are very likely. Travel in avalanche terrain is not recommended.

Another winter storm is hitting New Hampshire! As you can see from today’s High danger rating, this storm is expected to significantly impact snow stability on the mountain. The Observatory forecast is calling for 5-7” (12-18cm) of snow to fall today, and as the snow winds down the winds will ramp up and shift around clockwise from the S to the NW. By the end of the day wind speeds will be gusting over 80mph (130kph). This will load snow into all forecast areas and create very dangerous avalanche conditions. New windslab will build in an upside-down pattern.  It will start with lighter densities from the lower wind speeds, but as the winds begin to pick up slab densities will increase and lay heavier slabs on top of the lighter, weaker slabs. This is the notoriously unstable upside-down snowpack effect. In some locations slabs will start building on top of a very touchy soft slab surface layer left over from previous events this week. In addition to the new snow today, we expect the strong winds to be able to pick up and move snow that was already sitting above treeline from previous snowfalls this week. The bottom line is that very dangerous conditions will be developing today; travel in avalanche terrain is not recommended.

A lot is happening today in addition to the High avalanche danger. First, we have switched over to the Lion Head Winter Route. This route follows steep terrain; we highly recommend mountaineering skills and equipment for safe travel on the route (i.e. an ice axe and crampons.) Second, we have forecasted the Little Headwall and Lower Snowfields today. They had previously been “not posted.” The danger in the Lower Snowfields today comes primarily from above, with natural avalanches possibly running from the Duchess down into the Lower Snowfields proper. Although there is enough snow to warrant a forecasted rating today, the Little Headwall is not a good option for descending from the Bowl. The stream above is a long way from being filled in and skiable and the Little Headwall itself was only recently an open waterfall. Third, Arctic weather is coming in for the weekend. Check the Mt. Washington Observatory’s Higher Summits forecast discussion for the details. Testing yourself against the coldest temperatures we’ve seen here in a few years may sound glorious, but it doesn’t leave a big margin for error. Be conservative with your decisions this weekend. We’ll let you know more in the Weekend Update section of our website later this afternoon or evening. And finally, the John Sherburne Ski Trail has good coverage from top to bottom.

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 Ravine

Posted 8:45a.m., Thursday, January 20th, 2011

Tuckerman Ravine has both CONSIDERABLE and MODERATE avalanche danger.  The Sluice, Lip, Center Bowl, and the Chute have Considerable avalanche danger.  Natural avalanches are possible and human triggered avalanches are likely.  The Lobster Claw, Right Gully, Left Gully, and Hillman’s Highway have Moderate avalanche danger.  Natural avalanches are unlikely and human triggered avalanches are possible.  The Lower Snowfields and the Little Headwall are still not posted.

Huntington Ravine has MODERATE avalanche danger.  Natural avalanches are unlikely and human triggered avalanches are possible.  The only exception to this is the Escape Hatch which has Low avalanche danger.

The mountain’s veil of clouds continues to hide her secrets this morning as we are anxious to see the results of almost 1 foot of snow over the past 48 hours.  An occasional thinning of fog has given us a little peak but not enough to get really good information.  The brief glance shows the mainly south wind event has helped Dodges, Hillmans, and the Lower Snowfields quite a bit however Tuckerman still remains mostly clandestine under a cloak of clouds.  Over the past 24 hours the mountain received another 3” (7.5cm) of 7% density snow with generally very light winds.  Velocities have been increasing this morning with the forecast expecting them to reach 50mph (80kph) before dropping this afternoon and shifting from the NW to the W.  In the meantime upwards of another inch (2.5cm) in anticipated.  So the main issue today is around 3-4” (7.5-10cm) of low density snow loading into a variety of left over slabs from the main portion of the storm.  Any newly loaded snow today should be touchy soft slab potentially responding negatively to human triggers, aka-avalanching.  This is possible in areas posted at Moderate and likely in areas posted at Considerable.  Natural avalanches have the greatest potential in Tuckerman from the Sluice over to the Chute where they are possible.  Depending on what slabs still remain a fracture and failure could step down into these older layers.  The biggest question we still have is what avalanched and what didn’t.  We can confirm South and Odell ran with possibly other Huntington areas, but this cannot be corroborated.  Questions surrounding exact specifics of a number areas still exist so we are leaning on what historically occurs in certain locales with the past days weather and what atmospheric conditions should occur today.  We will be in the field today trying to fill in some of these data holes.  With this said another 2-4” (5-10cm) is expected tonight and tomorrow with winds ramping back up tomorrow afternoon.  It is also possible Friday that we may hit winds able to move existing snow from above treeline which would become another loading source for the Ravines. 

In addition to all this we are about to plunge into the deep freeze for the weekend, very deep,… going Kelvin perhaps.  The MWO staff is alluding to perhaps the coldest temps seen over the past several years for the higher summits.  Wind speeds will also be quite stiff so expect extreme conditions requiring experience, quality equipment, and very good judgment.  I just wanted to give you a heads up in advance, but we will be discussing this as it develops in tomorrow’s Advisory and the evening weekend update.  These cold conditions will also keep any snow instabilities lingering through the weekend in addition to new facet growth.

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

Avalanche Advisory for Tuckerman and Huntington Ravines

Posted 8:23a.m., Wednesday, January 19, 2011

All forecast areas in Tuckerman and Huntington Ravines have CONSIDERABLE avalanche danger today.  Natural avalanches are possible and human-triggered avalanches are likely.  Careful snowpack evaluation, cautious route-finding and conservative decision-making are essential.

For a while yesterday I wondered if the snow was actually going to amount to anything.  It seemed like it had been snowing all morning but there was little to show for it.  Sure, there were some drifts but it seemed like we had little more than a skim coat on the existing snowpack.  Luckily things picked up in the afternoon and by midnight the summit had picked up 8.3” (21cm) of snow with an average density of 7%.  Less than an inch has fallen up top since then but temperatures have remained below freezing.   At Hermit Lake we had 6” (15cm) of snow at the snowplot this morning but this only tells part of the story. The top inch (2.5cm) of the new snow is heavy and wet which leads me to believe that we picked up even more before settlement occurred.  How high up the mountain this wet layer extends will be the focus of our fieldwork in the coming days.  Hopefully it will get buried before it cools down and becomes a crust. 

Winds stayed out of the SSW, S and SE until 4AM this morning when they swung around to the WNW. Speeds during the heaviest snowfall yesterday were between 40 & 60mph (64 & 97kph) with a daily average at the summit of 46mph (74kph).  During this period aspects with a northerly component picked up a fair amount of snow through wind transport and if we weren’t socked in I’m sure we’d see evidence of an avalanche cycle.  These aspects received a Considerable rating today due to the possibility of human-triggered avalanches within the storm snow or at its interface with the old surface.  By midnight the winds were in steady decline and little oomph was left when they spun around to the WNW.  Southerly aspects saw limited loading during this storm event so why the Considerable rating there too you wonder?  Prior to this storm S aspects held the instabilities of most concern.  Some areas like the Lobster Claw, Right Gully and Damnation showed evidence of avalanche activity but all areas either reloaded or held “hangfire” (pieces of a failed slab that have hung on while the remainder avalanched).  Snow from the past 24 hours likely built a limited amount of new windslab in these areas but it did add additional load to already suspect slopes.  As temperatures drop today and snow showers continue these areas will be the first to receive additional loading if winds hang at the upper end of their forecasted range.  Easterly aspects have been cross-loaded by most of our recent storms and had one good period of direct loading before this event.  They will likely harbor the greatest spatial variability in terms of instability.  Concerns with human-triggered avalanches override our concerns with natural triggers in all areas today. 

The Sherburne Ski Trail has been providing great turns but a developing crust may impact your experience.  Watch your tips as the snowpack was thin to nonexistent just one week ago.  If you’re thinking of going to the summit in the coming days make sure you check back here to see the current status of Lion Head.  We’ll be making the shift to the Winter Route later in the week and if you’re watching the advisory you’ll be the first to know.

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 7:00a.m., Tuesday, January 18, 2011

Tuckerman Ravine: Hillman’s Highway, Left Gully, the Chute and Center Bowl will have HIGH avalanche danger today.  Natural avalanches are likely and human-triggered avalanches are very likely. Travel in avalanche terrain is not recommended.  All other forecast areas in Tuckerman will have CONSIDERABLE avalanche danger.  Natural avalanches are possible and human-triggered avalanches are likely. 

Huntington Ravine: North, Damnation, and Yale Gullies will have CONSIDERABLE avalanche danger today.  Natural avalanches are possible and human-triggered avalanches are likely.  All other forecast areas in Huntington will have HIGH avalanche danger today.  Natural avalanches are likely and human-triggered avalanches are very likely. Travel in avalanche terrain is not recommended.

Fog has engulfed the upper mountain, the temperature is on the rise and a storm is quickly approaching.  A Winter Storm Warning is in effect for the region as a warm front moves our way and snow approaches our doorstep.  We’re starting the morning with Low and Moderate avalanche danger in most areas but we’ll be climbing rapidly up the scale as the day moves along and the storm intensifies. The best news I’ve heard so far is that we’re expecting S winds with speeds that are ideal for transport and loading of snow.  Why would I be so excited for wind-loading out of the S you wonder?  The reason is that areas with N and NE aspects such as Hillman’s Highway, the Escape Hatch and South Gully are far behind their neighbors in development this season.  We expect to see a decent avalanche cycle run out of this storm and the areas that have so far been snow-deprived should reap the benefits. Avalanches will push farther than they have so far this season so you’ll need to use conservative decision-making to avoid being in the run-out.  The radar shows that it won’t be long before the snow starts and it is expected to fall through the day being especially heavy at times.  During this same period we should see a little more temperature rebound and the higher terrain should push into the lower 20’s F.  I expect that snow density will increase as the day moves along and with constant snowfall an upside-down layering will develop in the snowpack.  Heavier and denser slabs overlying lighter snow is a red flag situation in terms of snow stability.  The worst news that I’ve heard so far regarding the storm is that mixed precipitation is still in the forecast for tonight though the highest elevations may be spared.  This doesn’t bode well for the Rally to Restore a Crustless Winter.  The consolation is that snow should continue after the formation of said crust layer and hopefully bury it quickly.  Out of sight, out of mind is not a good guiding philosophy when concerned with snow science but buried crust is better than a surface crust if you want to make some turns!  We’re keeping our fingers crossed that colder air keeps the precipitation in purely snow form throughout the event but you can bet we’ll be watching for the crust in future field explorations. 

The Sherburne Ski Trail has been providing great turns and today’s storm will add to its excellence.  Get it before the mixed precip moves in for the best experience but watch your tips as the snowpack was thin to nonexistent just one week ago.  If you’re thinking of going to the summit in the coming days make sure you check back here to see the current status of Lion Head.  We’ll be making the shift to the Winter Route later in the week and if you’re watching the advisory you’ll be the first to know.

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 8:15a.m., Monday, January 17, 2011

Tuckerman Ravine: Hillman’s Highway and Left Gully have LOW avalanche danger.  Natural and human-triggered avalanches are unlikely in these areas but you’ll need to watch for pockets of instability on isolated terrain features.  All other forecast areas in Tuckerman have MODERATE avalanche danger.  Natural avalanches are unlikely and human-triggered avalanches are possible.  Evaluate the snow and terrain carefully if venturing out into these areas. The Lower Snowfields and Little Headwall are not posted due to a lack of snow.

Huntington Ravine: Central Gully has MODERATE avalanche danger.  Natural avalanches are unlikely and human-triggered avalanches are possible. All other forecast areas in Huntington have Low avalanche danger.  Natural and human-triggered avalanches are unlikely in these areas but you’ll need to watch for pockets of instability on isolated terrain features.  The Escape Hatch is not posted due to a lack of a snow.

Despite being in the clouds and blowing snow for all of yesterday the mountain picked up very little accumulation.  Less than 1” (2.5cm) fell in most locations but steady winds relocated much of the older snow that had been hanging around semi-protected areas above treeline.  Winds blew out of the W for much of the past 24 hours and blowing snow was reported at the summit during all hourly observations until early this morning.  Yesterday’s average wind speed was 53mph (85kph) but we’re now on the decline and expecting a drop to 30mph (48kph) as the day rolls along and winds hold out of the WNW.  Bluebird skies are allowing us to pick out some good visual clues and I’ve been watching a steady stream of low blowing snow pour into the start zones of the Lip and Sluice.  These areas create the most concern today and their smooth surface is indicative of recent windloading.  Just beside the Lip, the Center Bowl provides clues that less loading has occurred in the area even though it was in the direct lee of W winds.  While the Lip is on the upper end of the Moderate rating the Center Bowl is on the lower end.  Farther around the Bowl, Left Gully got blasted by the wind in the top of the gully but the bottom half has wind pillows that I’d keep an eye on.  Huntington is very similar to Left Gully in that most areas were scoured or received stabilizing benefits from recent winds.  Although most areas are rated as Low today you’ll still need to be alert for isolated instabilities such as below the ice in Pinnacle Gully.

The Sherburne Ski Trail is loving life after the last round of snow.  Many visitors have been enjoying its offerings but keep an eye out for buried hazards.  Things were grim before the storm so think light thoughts and graceful turns.  If you’re thinking of heading to the summit in the coming days keep an eye on the advisory as we’ll soon be switching to the Lion Head Winter Route and we’ll keep you posted.

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 Ravine

Posted 8:35a.m., Sunday, January 16, 2011

Tuckerman Ravine: The Sluice, Lip, and Center Bowl have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. All other forecasted areas of Tuckerman have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.  The Little Headwall and Lower Snowfields are not posted due to a lack of snow in these areas.

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

When I look outside at the weather today, I get this feeling down in my gut saying that things are all right in the world, as if everything is normal again. Well, maybe the rest of the world would disagree, but here on Mt. Washington we’ve got cold temperatures, a couple inches of new snow, and wind blowing it across the mountain tops. That seems right for mid-January. Just over 2” (5cm) of snow has fallen across all elevations with densities coming in between 3.6% and 5.2%, depending on where it was measured. Snowfall started with winds out of the SW that then shifted to the W and increased in speed overnight. Today they will shift farther to the NW and maintain their 40-55+mph (64-88kph) velocities. This combination of new snow and wind will cause the avalanche danger to trend upward today. The areas that are of most concern are those that are rated Considerable, the Sluice, Lip, and Center Bowl, as we believe in these areas the possibility for natural avalanche activity will exist. All other areas will also be creeping upward as wind loading continues. The critical variable for today is just how much loading will take place before the supply is exhausted. With the amounts of snow we’ve received and the forecast for clearing late in the day, we feel that some areas rated as Moderate will get into the upper end of that rating’s range. Examples of this are the Lobster Claw and Right Gully in Tuckerman, as well as Yale and Damnation gullies in Huntington. Other areas are starting from a point farther down on the danger scale, and therefore may not push the boundaries of what we’d call Moderate, but will still end up in the Moderate range nonetheless. It’s a good day to remember that avalanche danger is a dynamic process. You’ll need to be paying attention to the weather and assessing conditions as you go.

In addition to increasing avalanche danger today, the ravines will be in the fog for most of the day. This will make it more difficult to see the hazards from a safe distance. There are A LOT of potential human triggers running around on the mountain today—we’ve already seen nearly 100 people heading up Lion Head as of 8a.m.! Cold temperatures are also going to be a formidable opponent, so pack appropriately.

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 Ravine

Posted 8:15a.m., Saturday, January 15, 2011

Tuckerman Ravine: The Lobster Claw, Right Gully, Sluice, Lip, Center Bowl, 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. The Little Headwall and Lower Snowfields are not posted due to a lack of snow in these areas.

Huntington Ravine: North, Damnation, Yale, Central, and Pinnacle gullies have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. Odell and South gullies have Low avalanche danger. Natural and human triggered avalanches are unlikely. The Escape Hatch is not posted due to a lack of snow in this area.

After a fairly uneventful 24 hours of weather, avalanche conditions for the ravines today will be similar to yesterday with a mix of Moderate and Low danger. Wind speeds yesterday were in the single digits on the summit during the day, making the Bowl seem eerily calm and allowing us to get some good hands-on stability data. The latest storm brought about 16” (41cm) of snow to Hermit Lake, but it came with a slightly atypical wind pattern. What we have now are conditions that range from boilerplate hard old surface in the areas that were the most wind scoured (e.g. below the Chute and in much of Left Gully), to deep soft slab in heavily protected areas (e.g. some of the midsections of Right Gully and Lobster Claw). Spatial variability is once again a strong factor in snow stability. This means you’ll find that stability and conditions change quickly as you move around in the terrain. Although the variability is strong, there are a couple of consistent factors to help aid your decision making.

One consistency is related to which areas the recent snow was loaded into. Slopes and gullies on the northern side of the ravines received much more loading than those on the southern sides. Slopes in the central sections of both ravines had some cross-loading as well. Hillman’s Highway and Left Gully may have actually lost snow thanks to strong E and N winds. It’s the same story for Odell and South gullies in Huntington. The areas of most concern are those where new snow was loaded more deeply and was beyond the reach of yesterday’s solar gain. The sun wasn’t strong enough to affect the deeper instabilities or the aspects that aren’t directly facing south. The list of locations to watch out for includes the E-facing aspects in the Lip and Sluice, various parts of Right Gully and Lobster Claw, the tops of Yale, Damnation, and North, and the snowfields leading up to Central and Pinnacle. While this list isn’t comprehensive, my hope is that it helps you understand the degree of spatial variability that exists out there right now. You’ll need to continually be assessing stability as you move.

Another consistency is the New Year’s crust you’ll find underneath any new snow. Its depth will vary, but wherever you encounter it, the stuff is rock solid. Bury it under energetic slab and it can make for a great bed surface. In much of the Center Bowl and Chute this is less of a concern as it has bonded pretty well to the stiff slab above it. It can also be found at the surface in some locations; in these areas you’ll need to be ready to self-arrest immediately to avoid a rapidly accelerating 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 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 Ravine

Posted 8:59a.m., Friday, January 14, 2011

Tuckerman and Huntington Ravines have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The only exceptions to this rating are Hillman’s Highway and Left Gully in Tuckerman Ravine which have Low avalanche danger. In these areas, natural and human triggered avalanches are unlikely; however, you should watch for unstable snow on isolated terrain features.

We had a good storm on Wednesday, dumping 16” (41cm) of light density snow at the Hermit Lake snowplot. As great as that sounds, when I got a look into Tuckerman Ravine this morning I had to reset my expectations. Numerous small fracture lines can be seen around the ravines, however, in the aftermath the storm did not leave things looking as differently as I had hoped it would. A pattern exists for avalanche danger today that is similar in both Tuckerman and Huntington Ravine. Generally, the least amount of avalanche hazard will be found in the southern sides of the ravines, while the greatest avalanche danger is on northern slopes. In Tuckerman, Hillman’s Highway and Left Gully look much the same today as they did before the storm, hence their Low rating. On the other side of the ravine, in areas such as the Lobster Claw, Right Gully, Lip, and Sluice, new snow was able to hang on since the last avalanches ran through and they were more protected from the northerly winds. Cold weather is limiting the stabilization of these new slabs, even in the direct sunshine, and I would expect these areas to carry the greatest likelihood of a person triggering a slide. In the Center Bowl and Chute the slabs were more wind-affected than on the S-facing aspects, but not so much that they gained the strength they would need to be dropped farther down the rating scale. These areas also have the largest and most connected snowfields, which means you should be thinking not only about the snow you are traveling through, but also about the slabs you are connected to. Remember, the hazard today is directly related to human triggered avalanches. Options exist for avalanche-savvy mountaineers, but only if their willpower is strong enough to fight the tendency to be blinded to the hazard by the fresh snow and bluebird sky.

The distribution of avalanche hazard in Huntington is similar to Tuckerman. The northern gullies have the snow of most concern, particularly up high in the start zones of North, Damnation, and Yale. As you move from Central around to South there are fewer and smaller new slabs that were able to develop. Finding routes that entirely avoid unstable snow in the gullies is often hindered by the terrain in and leading up to the gullies, so pay attention to the changing conditions underfoot and view any new snow with suspicion. If you can find the hard icy old surface, that will be your best bet for avoiding stability problems.

We’ll be getting out into the field today, and this afternoon we’ll post thoughts for the upcoming weekend on our website, www.mountwashingtonavalanchecenter.org. We’ll also try to get some new photos up for your viewing enjoyment.

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 Ravine

Posted 7:40a.m., Thursday, January 13, 2011

All forecast areas in Tuckerman and Huntington Ravines have CONSIDERABLE avalanche danger today.  Natural avalanches are possible and human-triggered avalanches are likely. 

The mountain has received a healthy serving of snow from the cold Nor’Easter that just rolled through town but it looks like all snowfall will wrap up by midday.  The good news is that the Summit picked up 8.8” (22cm) of 5% snow by midnight last night and then almost another inch by 6 a.m.  The better news is that the lower part of the mountain picked up even more! The Hermit Lake snowplot had 16″ (41cm) as of 6:30am. Winds performed as expected sliding from the E through the NE and N before wrapping around to their current location out of the WNW at 54mph (87kph).  This allowed a combination of direct loading and cross-loading in most areas and when the clouds lift we expect to see evidence of the season’s biggest avalanche cycle.  Avalanche activity in the week prior to this storm had filled in much of Tuckerman’s floor allowing subsequent avalanches to push farther more easily.  Blowing snow will continue to make it hard to navigate this morning so you may not realize you’re in an avalanche runout path until it’s too late.  We’ve just come down from High avalanche danger and are sitting in the upper end of the Considerable rating. Natural avalanche activity is a strong possibility in the earlier part of the day due to the ongoing loading and cross loading of numerous slopes.

 I expect that when clearing occurs later today we’ll see a mixture of fracture lines, debris piles and wind-loaded slopes with reactivity to human triggers.  As the wind dies down later in the day and blowing snow no longer fills the air the potential for natural activity will decrease and human triggered avalanches will become the primary concern.  It is times like these that conservative decision-making is most important.  Sunny skies and the lure of fresh tracks is a dangerous combination immediately following a wind and snow event.

The John Sherburne Ski Trail is thankful for the recent snow.  Underneath the new blanket is a mixture of frozen crud, water ice, abrupt waterbars and bushy vegetation.  Keep those tips up and watch for wind affected areas.

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 Advisry for Tuckerman and Huntington Ravines

Posted: Wednesday, January 12, 2011 8:45 a.m.

Tuckerman Ravine: The Center Bowl, Lip, Sluice, Right Gully and Lobster Claw have HIGH avalanche danger.  Natural avalanches are likely and human-triggered avalanches are very likely.  Travel in avalanche terrain is not recommended.  All other forecast areas in Tuckerman have Considerable avalanche danger.  Natural avalanches are possible and human-triggered avalanches are likely.

Huntington Ravine: Central, Yale, Damnation and North Gullies have HIGH avalanche danger.  Natural avalanches are likely and human-triggered avalanches are very likely.  Travel in avalanche terrain is not recommended.  All other forecast areas in Huntington have Considerable avalanche danger.  Natural avalanches are possible and human-triggered avalanches are likely.

Finally a storm is upon us! We’re grateful even if it’s one that we would have taken for granted in past years as just another expected weekly event.  The Nor’easter hammering coastal areas should pick up its intensity in the mountains as the day progresses.  The higher summits of the Presidential Range are expecting 5-7” (13-18cm) of snow today with another 1-3”(2.5-7.5cm)  tonight and maybe even a little more tomorrow.  This is a bit colder of a Nor’easter than usual and summit temperatures will be around 5F (-15C) today, drop to 0F (-18C) tonight and then re-bound a bit tomorrow into the upper singles (F).  This translates into expectations for lower density snow which will make for easy transport and cold slab development.  Wind speeds will ramp up from the current 43mph(69kph) and push over 70mph(113kph) later today while they shift from the E to the N.  Anticipate this to cross-load S and N facing aspects during the first part of the day before directly loading S-facing slopes and cross-loading E aspects later this afternoon.  Avalanche danger will increase through the day taking most of the morning and early afternoon to reach the forecasts of High and Considerable.

Although certain forecast areas have not been posted at High remember Considerable is a substantial rating in its own right with natural avalanches being possible and human triggered avalanches being likely.  This is complicated by forecast areas in Tuckerman and Huntington Ravines being very close together, particularly the former.   As you transition from the Sluice, to the Lip, over to the Center Bowl and the Chute the aspects change, but their proximity allows avalanches to propagate into one another including criss-crossing run out paths.  As an example the Center Bowl is posted at High because we have concern a fracture in the Lip could propagate into the Bowl partially due to the cold elastic nature of expected slabs today.  However, just next to the Center Bowl is the Chute, posted at Considerable, which should receive less loading today but still contain formidable problems. To access this area you would generally need to travel under  other paths that are forecasted with High avalanche danger today.  The avalanche cycle of a couple days ago has filled in a lot of the Tuckerman floor so we expect avalanches to travel much farther than a week ago.  Once you pass the Connection First Aid Cache just before the ravine floor you are in avalanche terrain.   

This storm will reinvigorate the Sherburne Ski Trail but realize that before this storm most of the trail was ice and vegetation.  It’s not time to put away the rock skis yet!

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

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