Avalanche Advisory, Wednesday 1-11-2012

Expires midnight, 1-11-2012

Tuckerman Ravine has Moderate avalanche danger today. Natural avalanches are unlikely and human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features; evaluate snow and terrain carefully and identify features of concern. The exception to this rating is Hillman’s Highway and Left Gully which have Low avalanche danger. Natural and human triggered avalanches there are unlikely. Watch for unstable snow on isolated terrain features. Some areas are not yet posted due to the overall lack of snow. These include Lobster Claw, Right Gully, the Lower Snowfields, and the Little Headwall in Tuckerman. Forecasts for these locations will begin when conditions warrant.

Huntington Ravine has Low avalanche danger today.   Natural and human triggered avalanches are unlikely except in isolated terrain features. The Escape Hatch is not posted due to lack of snow cover.

Some more loose change fell yesterday as the nickel and diming continues with 1.4” (3.5cm) falling on the summit.  The mountain has seen snow everyday this month adding up to 11”(27.5cm) over the past 11 days averaging 7.4% in density.  Averaging an inch a day certainly isn’t much, but believe it or not, it has been making a difference.  Because the Ravines have been filling so slowly it hurts to see our precious accumulations over the past week an a half get taken away. But never the less, high West winds yesterday reaching 94 mph (153kph) did a fair bit of scouring across the mountain, particularly in the gullies of Huntington Ravine.  A few isolated pockets exist such as down low in Central, but overall stable conditions exist.  Because of their thin ribbon like nature Yale, Damnation, and North appear to have gone through the most dramatic change due to high wind velocities over the past several days.  Their exits are most notably scant of snow with a number of rocks and terrain features peppering the slopes.  All of this has led to the drop from Moderate to Low avalanche danger in Huntington.  In Tuckerman the lower slopes in the Ravine are most wind affected and are generally stable, but as you ascend in elevation areas of instability, protected from the high prevailing winds, are a concern.  New slabs below the ice in the Sluice, through the Lip, the Headwall ice, and over into the Chute above the narrows have triggered us to forecast a “Moderate” rating.  The Lip has most notably been protected from the high winds and its scouring effects, picking up new snow from edge to edge across its entire forecast area.  This slope and its adjacent pockets lead the concern for harboring unstable snow in the Ravines today. 

The big news is the weather event moving into the region tonight expected to give us “plowable snow”, as the weather service calls it.  It’s becoming clear that we will get something to enjoy, perhaps around 6-7 inches (15-17.5cm) delivered on SW, shifting to SE, winds.  This will affect north facing aspects the most on Thursday and into Friday morning.  Although it may be a bit premature to discuss Friday night I’ll mention it any way.  All models are showing a wind shift moving from the south to the west and increasing dramatically as we enter Saturday.  This would give us new problems as we enter the holiday, but more on that issue over the next 48 hours.  With the precipitation beginning after dark tonight you can expect an increasing avalanche danger tomorrow.

 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. Posted 8:45a.m. 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

1-11-2012 Print Friendly

 

Avalanche Advisory 1-10-2012

Expires 12:00 midnight, January 10, 2012

Tuckerman Ravine has Moderate avalanche danger today. Natural avalanches are unlikely and human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features; evaluate snow and terrain carefully and identify features of concern. The exception to this rating is Hillman’s Highway which has Low avalanche danger. Natural and human triggered avalanches there are unlikely. Watch for unstable snow on isolated terrain features. Some areas are not yet posted due to the overall lack of snow. These include Lobster Claw, Right Gully, the Lower Snowfields, and the Little Headwall in Tuckerman. Forecasts for these locations will begin when conditions warrant.

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

Today could turn out to be one of those days that rewards the observant and timely backcountry traveler. Field observations yesterday gave reason to believe some forecast areas had the potential to drop down a rating today. However, the today’s forecasted weather provides enough justification for keeping them where they’re at. So, if you’re out early and watching snowfall amounts closely, you may find better stability than the ratings would indicate. The key piece of information you should be looking for is how much snow has fallen. The Observatory and the NWS both indicate we may see up to 2″ of new snow today, riding in on W and NW winds that will ramp up to over 75mph (121kph). If this forecast plays out, yet another layer of slab will be deposited in various locations throughout the ravines. Strongly protected lee areas will have the best chance for this issue to arise. Coincidentally, these are the same locations that currently have some of the greatest stability issues. Examples include the growing snowfields in the steepest parts of the Lip and Center Bowl of Tuckerman. Also in Huntington Central Gully currently has and will receive the most snow loading. Other areas of Huntington (Yale, Pinnacle, and Odell to be precise) will start the day with Low avalanche danger. As snow and windloading commence they will rise back up to the Moderate rating. Of course, if we are fortunate enough to receive more than a couple inches then expect most areas to rise above today’s ratings.

At risk of sounding like a broken record, it’s worth mentioning again that the terrain features on the mountain and the relative lack of snowfall this year are creating conditions with a high degree of spatial variability. It would not be difficult to go into either ravine and find unstable snow. But move a short distance and the stability can change quickly. Careful route finding and constant stability evaluation can help mitigate the hazards under these conditions.

The John Sherburne Ski Trail is getting worse by the day. We generally don’t like to apply labels like “good” or “bad” to the conditions, but I’m throwing that idea out the window today. Sure it’s possible to ski down, but it’s in bad shape. Extremely thin cover, ample water ice, rock, brush, and abrupt waterbars might make you wonder if hiking down would have been a better idea.

 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.
  • Posted 8:10a.m., Tuesday January 10, 2012. 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

Tuckerman Ravine – Lip area of Tuckerman Ravine

A solo hiker died as a result of injuries sustained in a fall while descending in the vicinity the Lip area of Tuckerman Ravine. The fall was witnessed by the AMC caretaker at Hermit Lake Shelters, who immediately notified USFS Snow Rangers and initiated rescue efforts. Despite the fact that rescue was immediately begun, the victim passed away while rescuers were preparing for the evacuation.

Avalanche Advisory 1-9-2012

Expires 12:00 midnight, January 9, 2012

Tuckerman Ravine has Moderate avalanche danger today. Natural avalanches are unlikely and human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features; evaluate snow and terrain carefully and identify features of concern. The exception to this rating is Hillman’s Highway which has Low avalanche danger. Natural and human triggered avalanches there are unlikely. Watch for unstable snow on isolated terrain features. Some areas are not yet posted due to the overall lack of snow. These include Lobster Claw, Right Gully, the Lower Snowfields, and the Little Headwall in Tuckerman. Forecasts for these locations will begin when conditions warrant.

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

Ratings for today are identical to yesterday, though an additional 0.9” (2.3cm) of snow was recorded on the summit through yesterday evening. This makes for a total of 9.3” (27cm) for January at the summit Observatory, much less has been recorded at our Hermit Lake snowplot. The ravines are still broken up by bands of rock, brush, ice, etc, but the snowfields throughout the area are growing in size thanks to consistent wind transport of the snow that has fallen. On the whole, my concerns for today are primarily related to the 1.7” (4.3cm) of new snow that has fallen since Saturday. There were some stability issues lingering from before the weekend, however, the additional new snow and uppermost layers have surpassed these as the foremost stability problem. You should expect to see a variety of surface conditions depending on your location. In areas most exposed to winds you’ll find harder slabs that have more strength, while in more protected areas you can expect to find softer layers with less strength.

Considering the recent wind speed and direction, the protected areas where you will find the most unstable snow are the middle to upper sections of E and SE aspects. This includes the tops of Yale, Central, and Pinnacle in Huntington, as well as the Sluice, Lip, and Center Bowl of Tuckerman. Stronger winds from previous days had deposited snow into the lower sections of Huntington’s gullies as well. Use caution as you approach the climbs since these areas are often where climbers trigger avalanches. Also be aware that the broken up nature of the forecast areas is creating a highly variable snowpack within relatively small areas.

High pressure will be moving out today and more light snow may fall both during the day and through the overnight hours. I don’t expect accumulations to be much today, but tomorrow may be enough to raise the danger level. Later in the week a stronger system looks to be heading our way. Let’s all hope for cold temperatures to keep the precipitation of the frozen type.

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.
  • Posted 8:10a.m., Sunday January 9, 2012. 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

Descending the Tuckerman Ravine Trail in Winter

USFS Snow Rangers were heading home at the end of the day Sunday when notified of hikers having dialed 911 from Mt. Washington. Apparently, two hikers were attempting to descend the Tuckerman Ravine Trail through the ravine, when one of them slipped and fell. He was able to self-arrest, but somehow lost track of his partner. Thinking his partner had also fallen, he called 911 for assistance. After making the call, he was able to locate his partner above. He and his partner eventually found their way to and descended the Lion Head Trail. The HMC caretaker made contact with the party on the lower portion of the Tuckerman Ravine Trail, confirmed that they had made the distress call, and did not need further assistance.

Avalanche Advisory 1-8-2012

Expires 12:00 midnight, January 8, 2012

Tuckerman Ravine has Moderate avalanche danger today. Natural avalanches are unlikely and human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features; evaluate snow and terrain carefully and identify features of concern. The exception to this rating is Hillman’s Highway which has Low avalanche danger. Natural and human triggered avalanches are unlikely. Watch for unstable snow on isolated terrain features. Some areas are not yet posted due to the overall lack of snow. These include Lobster Claw, Right Gully, the Lower Snowfields, and the Little Headwall in Tuckerman. Forecasts for these locations will begin when conditions warrant.

Huntington Ravine has Moderate and Low avalanche danger today. Yale, Central, Pinnacle, and Odell have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. North, Damnation, and South gullies have Low avalanche danger. Natural and human triggered avalanches are unlikely. The Escape Hatch is not posted.

Today is starting out as a blustery foggy day in the ravines, but there is hope for some clearing this afternoon as high pressure slowly builds in. What we’re seeing this morning are the remnants of a weak weather system that dropped a small amount of snow across Mt. Washington late yesterday and overnight. A total of 1.1” (2.7cm) of light density snow was recorded on the summit. During this time, winds were from the west, blowing in the 50-70mph (80-113kph) range. New snow loading is contributing to today’s forecasted rating, as are the observations from our field trip yesterday. The snowpack on Saturday had some good strength to it in many areas, though there were also numerous locations that left me believing the snowpack remained in the lower end of the Moderate rating since human triggered avalanches were more “possible” than “unlikely.” Added to the lingering instabilities, we now have an additional layer of wind-transported snow to think about, as well as a slight potential for more snow this morning. While a meager inch of snow isn’t really all that much, the vast majority of the stability problems on this mountain are created by the ability of winds to multiply snowfall into much deeper slabs in lee areas. The potential weak layer and bed surface combination will change depending on where exactly you go.

The areas we’re most concerned with today are those in the lee of westerly winds. In Huntington, areas near the top of the approaches before the ice climbs begin may hold unstable slabs. Also expect to find pockets of snow in the tops of many gullies, including the ones that are rated Low today. In Tuckerman the Lip and Center Bowl would be the areas to be most concerned with. As you move through these locations you’ll find the snow underfoot changes quickly from place to place. We moved Left Gully up to Moderate today due to its ability to build slabs in the upper section under these ideal wind loading conditions. Today I believe an avalanche savvy traveler could work his or her way through many of the Moderate rated areas, but if you blindly head into steep terrain without paying attention to the snowpack you may very well trigger an avalanche.

The Sherburne Ski Trail took a hit yesterday with temperatures rising above freezing. Expect lots of brush and sections with water ice as well as breakable crust.

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.
  • Posted 8:30a.m., Sunday January 8, 2012. 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 (revised)

Avalanche Advisory 1-7-2012

Expires 12:00 midnight, Saturday, January 07, 2012

Tuckerman Ravine has Moderate and Low avalanche danger today. The Sluice, Lip, Center Bowl, and Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features; evaluate snow and terrain carefully and identify features of concern. Left Gully and Hillman’s Highway have Low avalanche danger. Natural and human triggered avalanches are unlikely. Watch for unstable snow on isolated terrain features. Some areas are not yet posted due to the overall lack of snow. These include Lobster Claw, Right Gully, the Lower Snowfields, and the Little Headwall in Tuckerman. Forecasts for these locations will begin when conditions warrant.

Huntington Ravine has Moderate and Low avalanche danger today. Yale, Central, Pinnacle, and Odell have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. North, Damnation, and South gullies have Low avalanche danger. Natural and human triggered avalanches are unlikely. The Escape Hatch is not posted.

Although down in the valley it certainly seems like winter snow will never arrive, Mt. Washington has recently been a different story. There has been measurable snow on the summit every day so far this year (7.6”/19cm in January) and winds have been doing an excellent job of moving the available snow into the ravines. This has put us firmly into avalanche-worthy conditions over the course of the past week. Two avalanche incidents took place this week in Huntington Ravine, and this morning evidence of natural avalanche activity can be seen in Left Gully and Dodge’s Drop. The crown lines from these are large enough to make me glad to not have been near them when they released.

Today the primary concern for people heading into the ravines will be human triggered avalanches on the existing slabs. These have been created over the last few days on strong winds from a mostly westerly direction. We have a widely variable snowpack overall. Areas that are often entirely covered with snow are currently broken up by rocks, ice cliffs, sub-ridges, etc. This is creating a situation where it is difficult to take information you collect in one location and extrapolate it to another. You’ll need to stay vigilant for changing conditions as you move from one patch of snow to another. For example, in the Center Bowl and Chute areas of Tuckerman you can find some areas where wind effect is prominent and other areas have softly loaded pillows of windslab. The Lip has filled in a lot lately, and although the whole area is still broken up by bands of rock and ice, the strong leeward aspect of this area has allowed snow to load onto the growing bed surfaces here. I would expect these snowfields to be some of the most reactive to human triggers. Remember that a lot of this recent snow is sitting in numerous crust layers from past weather events.

Areas posted at Low danger are not without hazard. Isolated pockets exist in many of these locations that may have instability issues. The top of Left Gully is one example, similar conditions exist in Huntington’s Low areas. In Huntington, the areas of greatest concern are the deposition areas at the top of the approaches, just before the ice climbing begins. Central, Pinnacle, and Odell all have areas of wind-loaded snow below them. Yale warrants a Moderate rating for a similar reason, but it is on the lower end of the spectrum.

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.
  • Posted 8:50a.m. January 7, 2012.  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

Print Friendly Advisory

Avalanche Advisory for Friday 1-6-2012

Expires at Midnight Friday 1-6-2012

Tuckerman and Huntington Ravines have CONSIDERABLE avalanche danger today.  Natural avalanches are possible and human triggered avalanches are likely.  The only exception to this is North Gully in Huntington which has Moderate avalanche danger.  We have not begun forecasting for the Lobster Claw, Right Gully, the Lower Snowfields, or Little Headwall in Tuckerman and the Escape Hatch in Huntington due to a general lack of snow in these areas.  Daily forecasting will begin for these areas when conditions warrant although avalanche activity may occur before this point.

As forecasted yesterday the higher summits were obscured by fog and blowing snow all day.  The summit reported 2.4” (6cm) of 7% snow on increasing winds from the West.  In the mid afternoon velocities peaked at 89 mph (143 kph) vastly exceeding expectations.  This was also the period of maximum snow loading into the Ravines.  Snow will continue today with up to another 3” of new accumulation carried in on West winds with speeds from the current of 35mph (56kph) to over 70mph (112kph) this afternoon.  This will generate some heavier denser slabs through the day over some loose unconsolidated snow and very soft slabs deposited this morning.  This is particularly true in strong lee areas protected from W winds.  This is all occurring on top of the issues that built through the day yesterday which caused yet another avalanche accident in Huntington Ravine late in the day.  Areas in the direct lee of West winds will be the primary areas of concern earliest today with adjacent aspects following behind.  The Lip through the Center Headwall and over to Left Gully would be the focus locations to worry about in Tuckerman while over in Huntington Ravine Odell, Pinnacle and Central will have more instability issues than gullies such as Yale or Damnation.  It’s important to remember that each forecasted rating is not a point on a line but a spectrum.  Some outlying aspects will be on the lower end of “Considerable” while others may be in the middle or upper end of the definition.

There is little doubt that we will have unstable snow issues today and into the weekend.  More snow tonight and tomorrow may deposit another 2-3” (5-7.5cm) on 40-70mph (64-112kph) winds along with increasing temperatures making for heavier snow, therefore denser slabs.  The slow accumulation over the past week will add up to around a foot (30cm) of accumulation over the past 7 days by tomorrow which can be a little trickier to deal with than a big dump.  This scenario often lets multiple layers to develop with just enough strength to stay put waiting for a trigger.  In a big storm avalanche cycles usually occur because the snow strength can’t handle the rapid load.  Because of the multiple layers out there you will need all your avalanche senses and skills today and through the weekend.  Expect to find a mix of conditions such as some scouring down to old bed surfaces in areas open to wind hammering right next to unstable slabs.  I would prepare for widespread instabilities perhaps above you or adjacent to your position.  We will have some avalanche incident discussion on our Incident page today as well as in the “Weekend Update” this afternoon.  So check back to learn more about the upcoming weekend and lessons learned from the 2 avalanche accidents/incidents this week on www.mountwashingtonavalanchecenter.org .

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. Posted 8:50.  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

1-6-2012 Print Friendly

Huntington Ravine – Central Gully

A party of two was climbing Central Gully when the leader was hit with a naturally-triggered sluff avalanche. During the fall, one of the climbers fractured his ankle. Much of the information below was gathered from a narrative provided by a guide who was in the area as well as from conversations with the injured party.

Just prior to the incident, the guided group climbed up to top of the ice bulge in Central. The guide decided not to continue up the gully due to excessive spindrift, blowing snow, and generally harsh conditions above treeline. He had a 3-ice screw anchor built for his group in the ice. When the party of two arrived, he allowed them to clip the anchor while they climbed the ice. However, after the group cleared the ice they were climbing unprotected with a short rope between them.

At this point the guide was at the top belay, out of the fall line, while his clients were down at an ice screw anchor below the ice and also out of the fall line. About 15 meters above the ice, the party of two was hit with a loose snow (sluff) avalanche which carried them both downslope. According to the leader, the force felt as though he received a stiff push or kick in the chest. The guide heard “Avalanche!” but did not see the falling climbers pass by. He descended down to his clients to get them situated. He assumed that the slide had happened below him and that the party of two was still up in the gully. About 10 minutes later he heard a call for help. The party had fallen about 100m, coming to rest about 30m below the fracture line from two days earlier. It was the second climber who sustained the ankle injury. The lead climber was uninjured but did break his climbing helmet in the fall. It wasn’t until he descended to the injured party that he learned it was the climbers above who had been avalanched past.

With help from his clients and the partner of injured climber, the guide was able to lower the patient down toward the bottom of the fan. At this point two clients went to the rescue cache to bring up a litter. The guide had been able to wrap the patient in a bivy bag and help keep him warm with a water bottle of hot tea placed between his legs. The patient was then placed in the litter and they worked their way down to the Harvard Cabin. From the time of the accident (2pm) to the time they arrived at the cabin (6pm) was about 4 hours. Their efforts are very much appreciated, since the trail from the bottom of the fan to the Cabin is very difficult for a litter carry in these lean snow conditions.

USFS Snow Rangers met the group at the Harvard Cabin, reassessed and re-splinted the injured leg. From arrival at the cabin to the parking lot at Pinkham was about 2 more hours. The litter was sledded down the Sherburne Ski Trail by USFS Snow Rangers, MRS and students from SOLO who were at Pinkham for a Wilderness First Responder course.

We received word afterwards that the patient did indeed break his ankle, which will require surgical repair. This day (January 5) was the first 5-scale avalanche advisory for Huntington Ravine this season. The advisory for the day indicated Huntington Ravine starting the day at Low danger, but moving into the Moderate rating as a forecasted 1-3” loaded in on W and NW winds. The summit did record 2.4” of new snow on January 5 with winds averaging 56mph.

Avalanche Advisory for Thursday 1-05-2012

Expires tonight at Midnight 1-05-2012

Tuckerman and Huntington Ravines have Moderate avalanche danger today.  Natural avalanches are unlikely and human triggered avalanches are possible.  We have not begun forecasting for the Lobster Claw, Right Gully, the Lower Snowfields, or Little Headwall in Tuckerman and the Escape Hatch in Huntington due to a general lack of snow in these areas.  Forecasting will begin for these areas when conditions warrant although avalanche activity may occur before this point.

This is about the latest 5 scale danger rating initiation for a season I can remember but the mountain finally thought it was about time, giving us enough snow to begin.  Over the past 6 days we’ve picked up snow daily adding up to 6.5” (17.5cm) on mostly SW to NW winds.  It is always impressive to see the Ravines’ lee terrain change so much from this nickel and diming precipitation.  This morning both Ravines are beginning at Low avalanche danger but the 1-3 inches (2.5-7.5cm) that are forecasted on W to NW winds from 45-60+mph (72-96+kph) should load lee slopes with new cold, low density snow.  Therefore expect changing conditions through the day and anticipate the steepest and largest slopes in the direct lee to be the most affected.  I would expect a number of locations to be on the upper end of the Moderate rating if the predicted snow accumulations become reality.  Due to the size and track length of a number of locations we decided it was time to move to a daily advisory.  Today’s weather forecast clinched it. The Chute and Left Gully are well ahead of neighboring locations in terms of size and development for issues in Tuckerman.  In Huntington Yale, Central and Odell are the most prominent areas of concern followed by the exits in South, Pinnacle and Damnation.  An area not mentioned above, but one that requires constant attention is the Lip through the Center Bowl of Tuckerman.  This area has many snow fields, benches, and pockets isolated from one another by ice and rock, many harboring very different conditions from patch to patch.  The degree of protection in the lee, the thickness of slabs, the size of each pocket all effect their stability.  Temperature gradients have also been high due to recent cold air.  This has created varying degrees of facet growth particularly in areas with thin snow coverage and a number of terrain features like rock and ice above and below the surface.   Up to another couple of inches (5cm) is expected tomorrow, once again on perfect loading W-NW winds so anticipate some stability issues to exist for the weekend if this plays out.  Also pay attention to a very icy trail from Pinkham to Hermit Lake.  New snow will help if we get enough, but could also hide slippery sections.  Micros spikes, ski poles or crampons may all be helpful.  Be sure to:

  • Check the avalanche advisory now posted daily due to the new snow forecast. 
  • Read the Weekend Updated posted tomorrow (Friday) afternoon/evening. 
  • Read a lesson learned summary on our incidents concerning a party of 2 skiers that were avalanched in Huntington’s Central gully on Tuesday with pictures and some analysis. 
  • Look at a number of pictures posted showing the Ravines and snow coverage that we took yesterday.

Check our website www.mountwashingtonavalanchecenter.org through the day uploading these bullets.

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.  Posted 8:20am. A new advisory will be issued tomorrow.

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

1-5-2012 Print Friendly