Avalanche Advisory for Wednesday, 2-29-2012

This advisory expires at midnight Wednesday, 2-29-2012

Tuckerman Ravine currently has MODERATE and LOW avalanche danger. The Sluice, Lip, Center Bowl, and Chute have Moderate danger.  Natural avalanches are unlikely and human triggered avalanches are possible.  The Lobster Claw, Right Gully, Left Gully, Hillman’s Highway, the Lower Snowfields and the Little Headwall have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

Huntington Ravine currently has LOW avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. 

On this final day of February, in a leap year, the Snow Rangers are celebrating an extra day of winter with the hope it will help our annual snow total.  Wishful thinking you say?  Well read on to hear about the impending storm moving in today.  Over the past 24 hours the summit only received 0.3” of new snow with moderate NW winds which obviously didn’t add to many avalanche instability issues.  All areas dropped a rating from yesterday with the main concerns living in the Center Bowl, Lip, and Sluice.  The fracture lines from last weekend’s storm continue to slowly fill.  This aids us to quickly determine how much these general areas are picking up with a quick look through the binoculars.  Overall, there are some instabilities to recognize today, but the real problems won’t develop until very late in the day with the intrusion of our next weather maker.  A WINTER STORM WARNING is in effect from 7pm tonight to 9pm Thursday evening.  The system moving from the S will give us a chance of afternoon snow before the main precipitation shield envelops the mountains.  Snow totals are expected to be heaviest in the southern part of the state where a QPF (expected water equivalent) of 1.0” is higher than the 0.7” for our region.  One thing the North Country has going for it is colder air, adding to our “fluff factor”, as the NWS calls it.  In total 6-10” of snow is a reasonable expectation by the time it shuts down.  This storm will be delivered on light to moderate S to ESE wind from 10 to 40+ mph.  This won’t have the usual loading factors we see with our prevailing westerly’s so expect Hillman’s Highway, Left, the Escape Hatch, South, and Odell gullies to be our main forecast areas of concern tomorrow.  We will have cross loading issues in some areas, but that will be greatly determined by how high our wind speeds become.  Although the weekend is still many weather model runs away, they currently are highlighting some shifting and increasing wind which are concerns for me.  Winds are expected to stay light to moderate, for Mount Washington, until Saturday when a W or NW will may hit +/-80mph overnight giving us a significant loading event.  More on this potential avalanche issue in the upcoming days. 

Summarizing, in areas at Low danger you will find old surface with numerous pockets of softer snow which can be easily avoided by a skier, rider or climber that’s paying attention to the terrain.  Areas at Moderate harbor more issues due to the last 3 days of loading and 1.7” of snow.  The winter storm will start giving us snow this afternoon but should not affect avalanche danger today during daylight hours if the forecasted timing is on the mark.  Be ready to adjust your plans if it begins earlier than very late today.  The intensity will pick up during the early morning hours with up to a few inches on the ground by dawn.  Snow will fall through Thursday increasing the avalanche danger.  Expect “Considerable” or higher to be issued in tomorrow’s advisory.

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 8:35a.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
www.mountwashingtonavalanchecenter.org

2012-02-29 Print Version

 

Avalanche Advisory for Tuesday, 2-28-2012

This advisory expires at 12:00 midnight, Tuesday, February 28 2012.

Tuckerman Ravine has CONSIDERABLE and MODERATE avalanche danger. The Sluice, Lip, Center Bowl, and Chute have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. Lobster Claw, Right Gully, Left Gully, Hillman’s Highway, and the Lower Snowfields have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Little Headwall has Low avalanche danger. Natural and human triggered avalanches are unlikely.

All forecast areas of Huntington Ravine have MODERATE avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. 

Today is a day of changing avalanche danger. Yesterday’s weather forecast for 1-3” didn’t quite pan out as we had hoped, with just 1” of silky 10% density snow falling at Hermit Lake. This is OK, though, because any snow is better than no snow this season. Late yesterday morning, winds began to transport snow around Tuckerman Ravine. This snow was leftover from the weekend storm and was made available for loading by a slight shift in wind direction. Fracture lines in the bowl were refilling even before any new snow began to fall. Later in the afternoon, when light snowfall started, the winds also began to accelerate. This trend has continued to the present time, with winds blowing even stronger than the morning forecast (currently gusting over 100mph/162kph) and light snow flurries still in the air. All this is adding up to the idea that there is sufficient loading taking place at this time that you should be thinking about naturally-triggered avalanches being possible in some locations. The Sluice definitely has my attention, since we believe it did not avalanche during the weekend cycle while slopes on either side of it did. Adding another layer of new slab on top might be just the load it needs to fracture and fail. As I mentioned in yesterday’s advisory, getting into an avalanche in the Sluice would carry severe consequences due to the terrain traps in the runout below. Additional loading on the bed surface in the Lip and Center Bowl could also produce naturally-triggered avalanches today.

The changing part of this forecast has to do with the high pressure system that is expected to take hold and clear the mountain of its foggy shroud. As this moves in, wind speeds will be decreasing, which is a two-sided coin in this situation. Current wind speeds are doing a good job of scouring new snow out of many forecast areas, but as speeds diminish, the rate of slab development will increase. This will continue either until there is no longer any snow available for winds to move, or until wind speed drops off significantly. The safe bet today is to expect further wind loading to be taking place until visibility improves and shows you that the loading is over. By the end of daylight hours, I think the Considerable rated areas will have dropped down into Moderate territory, but that still means there is the possibility of a person triggering an avalanche. I also think there might be some areas of Huntington and Tuckerman that won’t hold onto much new slab. If this is the case, late in the day the hazard in these areas would be dropping as well. Until visibility improves, you won’t be able to determine whether or not this has happened. Basically, if you’re staying on the hard old surfaces you’ll avoid instabilities altogether.

I had the not-so-fun experience yesterday of trying to ride a snowboard out through the Little Headwall. Attempting this in its current state will put you into bushwack to avoid the open streambed, followed by a couple turns on the Little Headwall to avoid the open water hole, then down into slightly more open bushes down below. You’re not missing much by taking the hiking trail down. Maybe some new snow on Wednesday night and Thursday will change things here, but I’ll believe it when I see 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.  
  • Posted 8:35am. 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

2012-02-28 Print Friendly

 

Avalanche Advisory for Monday, 2-27-2012

This advisory expires at 12:00 midnight Monday, February 27, 2012

Tuckerman Ravine has MODERATE and Low avalanche danger. Right Gully, the Sluice, the Lip, the Center Bowl, and the Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. All other forecast areas have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

All forecast areas of Huntington Ravine have LOW avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

Remember this past weekend? Those were good times, eh? After all the fun, today certainly feels like a Monday morning. The excitement of a good snowstorm has passed, avalanche danger has subsided quite a bit, and the threat of clouds lowering is putting a gray feeling on the day. But if you’re a snow junkie, take comfort in the 1-3” (2.5-7.5cm) that are forecasted to fall later this afternoon and tonight. This snow is worth paying attention to, particularly if you’re going to be out on the mountain after dark, but I don’t think it will start early enough to affect stability today. Current conditions will remain for the daylight hours. Anticipate rising avalanche danger after snowfall begins to accumulate.

Yesterday, we were able to get into both ravines for a look at the aftermath of the weekend avalanche cycle. Huntington had slides in Pinnacle, Odell, and South. Much of the terrain in Huntington at this time is either old surface, bed surface, or wind-hammered snow, hence the Low rating. The strong winds that took place throughout much of the storm didn’t let a lot of snow stick to the gullies. The northern gullies have very little snow left in their upper sections.

In Tuckerman, slides were noted in Hillman’s, Duchess, Left Gully, Center Bowl, the Lip, and Right Gully. The one prominent location that appears to have not slid is the Sluice. Interestingly, the surface texture in much of the Sluice is almost identical to what you’ll see above the crown lines in the Bowl and Lip. I would treat this area with a healthy dose of caution. There are many bushes that were recently buried here, which often act as weak points in the slab. Judging from the thick debris in the floor from the Lip and considering that the runout is an enormous pile of boulders (i.e. Lunch Rocks), an avalanche in the Sluice would be a tough one to walk away from. The crown line(s) in the Lip and Center Bowl have reloaded to some extent. In these areas the Moderate rating is based on hangfire as well as the new loading on the old bed surface. In the aftermath of these avalanches, spatial variability takes on a whole new meaning. In Right Gully and the Chute, there is a mix of wind scouring and wind loaded areas. Climbers may find it easy enough to avoid the areas of greatest instability, but the lack of good snow in stable locations might cause a skier and snowboarder to gravitate toward the unstable snow. Finally, in Hillman’s, as well as the other areas rated at Low, expect isolated pockets of unstable snow. Hillman’s has a lot of old surface exposed, but also has numerous patches of newer slab on top of it. Left Gully was hammered by the winds and has good stability. And, the entrance into the Little Headwall is finally filling in with a reasonable amount of snow. There are still open water holes and some that were just recently covered, so use caution in this area. After this morning’s trip into Tuckerman I’ll try to post some pictures onto our website to show you what all this looks like.

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 8:55am. 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

2012-02-27 Print Friendly

Avalanche Advisory for Sunday, 2-26-2012

This Advisory expires at Midnight Sunday, 2-26-2012

Tuckerman and Huntington Ravines have CONSIDERABLE avalanche danger.  Natural avalanches are possible and human triggered avalanches are likely. Dangerous avalanche conditions exist.  Cautious route finding and conservative decision making is essential.  The only exception to this rating is the Little Headwall, which has Moderate danger.  Thin areas and some holes into the brook still exist

While the storm wrapped up in the valleys yesterday upslope snow kept chucking snow in the high mountains giving up an additional 4.8” (12cm) on the summit.  Very high winds didn’t quite get to where we thought they might, but it came darn close, gusting over 100mph (160kph) with a maximum of 107mph.  Snow showers finally shut down early this morning. High velocities for most of today will continue with some loading.  The whipped low density crystals are being pulverized, creating an aerosol shield over the mountain.  Visibility is still very limited so we are getting anxious to see the aftermath of this storm which delivered 10” to the summit and about 13” (32.5cm) at Hermit Lake.  A brief window of visibility allowed us to see a debris pile at the bottom of Hillman’s Highway and a large crown line in the Tuckerman Bowl through the Lip before a veil of secrecy cloaked the Ravine once again.  Being conservative for at least another day would be a good idea.

Between the continued loading and the inability to completely substantiate what avalanched and what is still on steep slopes waiting, we can’t rule out the possibility of natural avalanches today.  In Tuckerman, I believe we have just come down from yesterday’s “High” rating so expect a solid or upper end of “Considerable” to be the starting point in numerous locations this morning.  In Huntington, you should find much more variable conditions with scoured surfaces in some of the ‘wind tunnel’ sections of gullies and pillowed up snow in others.  The lower end of the Considerable rating is the probable situation in this, more northern Ravine.  Again, loading is continuing due to high NW winds so if snow movement does shut down it won’t happen until very late in the day.  Cold air below zero F (-18C) will keep slabs from consolidating much, allowing instabilities to survive particularly in areas sheltered from high winds.  Other slopes exposed to today’s high winds may be kept scoured clean and will likely continue to become wind hardened, helping stability slowly increase.   Ultimately, you should find a high degree of slope scale spatial variability; hard old surfaces in some locales; hard new Styrofoam in others; and deeper new soft slabs as you get into the strong lee of protected terrain.  I say all this because with limited visibility you won’t have sight to aid your assessment of what is above you.  Expect differences, changing surface conditions and varying degrees of snow instability.  It is also Sunday, the last day of vacation week, so expect a number of human triggers to be running around.  If you are one of those triggers descending into soft slab on a popular route anticipate the potential of others below you shrouded by clouds and snow.  Also expect a brutal day above treeline with negative temperatures and very high winds.    

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 8:35a.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
www.mountwashingtonavalanchecenter.org

2012-02-26 Print Version

 

Avalanche Advisory for Saturday, 2-25-2012

This avalanche advisory expires at midnight Saturday, 2-25-2012

All forecast areas of Tuckerman and Huntington Ravines have HIGH avalanche danger.  Natural avalanches are likely and human triggered avalanches are very likely. Travel in avalanche terrain is not recommended. This forecast also includes the Lower Snowfields, which are posted at High danger, and the Little Headwall, which is posted at Considerable danger today.

Well, it’s actually happened. We got a real, bona-fide snowstorm last night. That makes me wish I could call in sick and go ski the Mt. Washington Valley Chocolate Festival tour, but I’ll settle for working on Mt. Washington as a consolation. Since it began, the summit has recorded 6.3” of 10% density snow. It seems like we have a little more than that down here at Hermit Lake, but our snowplots were affected by wind so the data is a little off. I’d estimate about 8” has fallen. Down at Pinkham Notch we measured 7”. An additional 1-2” is forecasted to fall during the day. Looking at the higher summits wind forecast, the avalanche hazard becomes pretty clear to us: we expect to have avalanche activity in numerous locations, perhaps some even sliding multiple times throughout this event. The higher density snow and wind velocities lead me to believe we could see some large hard slab avalanches. These are not the soft fluffy kind you see in the ski movies; they’re the kind that can snap trees like matchsticks and they can travel farther into the runouts than previous slides have this season. We do not recommend traveling into avalanche terrain today, even just to the floor of Tuckerman or into the fan area of Huntington.

Travel above treeline this weekend will be challenging, to say the least. As the weather system progresses, WNW winds will ramp up to speeds easily gusting in excess of 100mph. You’ll be in the clouds starting well below treeline, and blowing snow will significantly hamper your visibility as you attain treeline. In addition to low visibility and strong winds, temperatures will be falling through the day to an overnight low of -10F. If you want to venture up high, do so with a willingness to turn around and head downhill when needed.

You may have noticed that we began forecasting the Lower Snowfields and the Little Headwall today. The Lower Snowfields will likely have avalanche activity coming into it from the Duchess and Dead End Gully above, but could also have avalanche activity from within the snowfields themselves. The Little Headwall holds the lowest stability hazard for today. Strong winds are ideal for loading slabs into this area, and we certainly have those today. Should you be unfortunate enough to be caught even in a small slide, there is a chance you’d end up in an open hole in the river. Tomorrow, clouds and snow will clear out, but the winds will remain very strong and temperatures cold. I would expect that most of the forecast areas rating will decrease. Some, such as in Huntington, may even go down to Low danger due to avalanches and wind-scouring. Other areas may go down to Considerable or Moderate. Be sure to check the advisory tomorrow morning, and equally important, check the weather forecast before heading out.

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 8:35am. 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

2012-02-25 Print friendly

Avalanche Advisory for Friday, 2-24-2012

This avalanche advisory expires at midnight Friday, 2-24-2012

Tuckerman and Huntington Ravines have MODERATE avalanche danger.  Natural avalanches are unlikely and human triggered avalanches are possible.  Heightened avalanche conditions exist on specific terrain features.   Evaluate snow carefully to identify these areas of concern.  Many caveats exist today so read on for details below. The Lower Snowfields and the Little Headwall are not posted due to an overall lack of snow although they are getting close. Forecasts for these locations will begin when conditions warrant.

Over the past 24 hours the summit received 2.3” (5.75cm) of new snow which adds up to 3.9” (10cm) over the past 2 days.  New snow was delivered on a shifting and increasing wind which peaked yesterday afternoon from the NW at 81mph (128kph).  This loaded most of our avalanche terrain across both Ravines with numerous new slabs.  Early this morning the summits cleared offering some brief visibility before they become socked in again with the approaching weather system.  This event has put the region under a WINTER STORM WARNING from 1pm this afternoon until tomorrow morning.  At our forecasters meeting this morning we had a good discussion on how to handle the danger ratings today with the approaching precipitation and exact timing of new snow.  We feel “Moderate” covers the reality of current instabilities this morning well, in Tuckerman particularly from the Sluice over to the Chute which harbor our most significant concerns.  Of all our forecast areas we believe a human trigger has the greatest possibility to cause the fracture and failure of slabs in the strong lee areas created by the high W and NW winds on Thursday. In Huntington, Central and Yale are currently at “Moderate” with the other gullies sitting at “Low” danger as of 7am, but these should come into the “Moderate” rating late this afternoon pushing dusk.  Unstable pockets can be found in these “Low” locations this morning however they can be avoided by a mindful climber.  

As light snow begins to fall as early as this morning it will be associated with very light SE winds from 10-25mph (16-40kph) and increase to 35mph (56kph) through the day.  During day light hours we aren’t expecting much more than an inch …maybe two (2.5-5cm) of new snow blanketing the mountain.  Snow will intensify this evening with a building wind that will wrap and blow from the W.  If you adhere to the strict timing of this advisory lasting to midnight, the “Moderate” rating should be busting at the seams by that point.  Natural avalanche potential will be building after darkness with the definition of “Considerable” coming into play in some places before pumpkin time at 12 midnight.  This transition should occur so late in today’s advisory window that calling areas “Considerable” would be overstating the situation for daylight today, hence the “Moderate” forecast.  

It would be a very good day to be conservative in your overall plans to absolutely assure you are not benighted.  As snow intensifies overnight the higher mountains should hit somewhere between 6” and 10” (15-25cm) with winds ramping up substantially, raging to around 110mph (176kph) from the WNW on Saturday.  With this scenario I could envision the mountains reaching maximum instability, with “High” danger conditions, between 2 and 6am Saturday morning before subsiding slightly for the meat of Saturday.  For all of this to play out as described, timing is everything!  The main bulls-eye points to remember are as follows; 1. We are on an increasing avalanche danger trend beginning later this afternoon; 2. A “High” danger will likely be achieved sometime before the Saturday avalanche advisory issuance; and 3. Expect full arctic extreme conditions above treeline on Saturday as temperature hover around zero F and winds gust to 110 mph (176kph); 4. It will be critical to read Saturday’s Avalanche Advisory before heading up the mountain tomorrow and suggested you read our Weekend Update early this evening.

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 8:35am. A new advisory will be issued tomorrow.
  • Print friendly version

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

Avalanche Advisory for Thursday, 2-23-2012

This advisory expires at midnight, Thursday 2-23-2012

Tuckerman Ravine will have CONSIDERABLE and MODERATE avalanche danger today.  The Sluice, Lip, Center Bowl, and Chute will 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 not posted due to an overall lack of snow, but are getting closer. Forecasts for these locations will begin when conditions warrant.

Huntington Ravine will have MODERATE avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.

Over the last 24 hours the summit picked up 1.6” (4cm) of new snow delivered on W winds peaking at 77mph last night around 10pm. Today’s avalanche ratings are taking this accumulation and the 2-3” (5-7.5cm) forecasted for today into account.  Light snow recently began right on schedule with the 2-3” expected mostly to fall this morning and in the early afternoon.  As this system gets ushered off to the East, winds will accelerate, gusting over 80mph later today.  As all of this occurs a wind shift will also transpire, moving from a SW direction early this morning to the NW.  If this forecast comes to fruition new snow will be deposited in all our primary avalanche start zones in both ravines as winds walk a full 90 degrees on the compass rose.  This new loading will commence first with those aspects having a north facing component, moving through eastern aspects during the late morning, and then finishing with southern faces later today when winds move to the NW.  I would expect gullies facing towards the E and SE, such as the Center Bowl, Lip, and Sluice in Tuckerman and Odell, Pinnacle, Central, and Yale in Huntington to move to the upper end of their rating definitions if we end up on the high side of the expected snow totals and wind velocities.  As this occurs a number of Moderate danger forecasted areas will increase their potential for natural avalanches so we maybe running the fine line between the words “unlikely” and “possible” later today.  A slow transition from the end of one danger rating into the beginning of the next can be hazy so evaluate stability continuously today and be ready for an increasing avalanche danger.   In steep locations I would expect sluffing to occur beginning later this morning building up snow below sections of water ice such as under the Headwall ice in Tuckerman and the ice in Odell and Pinnacle gullies in Huntington.

Tomorrow the higher elevations will get more snow while the valleys likely deal with a lovely mix of snow and rain.  On Mount Washington and the rest of the Presidentials the potential for some respectable snow accumulations is becoming more certain with each weather model run.  The latest data is expecting 6-8” (15-20cm) with some locations getting upwards of 10” (25cm) associated with a SE and S wind.  Total melted water from precipitation over the next 48 hours should total between 0.8 and 1.0” (2 and 2.5cm). Expect an increasing avalanche danger with a good chance for some areas posted at “High”.  At this point, with the forecasted snow and the drop in temperatures expect a number of lingering avalanche problems into the weekend.  In addition, until widespread snow covers the hard icy surfaces expect some challenging travel in steep terrain without traction devices for your feet.  Crampons, an ice ax and good self arrest skills are necessary for safe travel.  Many fall lines are peppered with rocks, brush and other unfortunate body stoppers so consider your travel routes well and think about who might fall above you this busy holiday week.  

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
  • Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast.
  • For more information contact the Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or the Harvard Cabin.  
  • Posted 8:15a.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
www.mountwashingtonavalanchecenter.org

2012-02-23 Print Version

 

Avalanche Advisory for Wednesday, 2-22-2012

This advisory expires at midnight Wednesday 2-22-2012

Tuckerman Ravine has MODERATE and LOW avalanche danger.  The Sluice, Lip, Center Bowl, and Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lobster Claw, Right Gully, Left Gully, and Hillman’s Highway have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. The Lower Snowfields and the Little Headwall are not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

All forecast areas of Huntington Ravine have LOW avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

As a Snow Ranger I must say I’m a little embarrassed to be this excited about the next few days of snow, but it’s been so lean this season I should just let a little joy happen.  A trace to 2” today, 1-3” tonight, and 1-3” tomorrow may be followed by a whopping boot top 5” on Friday!  This doesn’t measure up to a hard hitting storm, however the day to day amounts can add up if we see the higher end of snow expectations.  Well…. back to today.  A trace to 2” (5cm) of snow is forecasted for daylight hours today delivered on W winds blowing at 45 to 60mph (72-97kph) gusting over 70mph (112kph) this afternoon.  In areas posted at Low you should expect isolated pockets of instability to develop in strong lee terrain features especially in east facing aspects and some other cross loaded locations.  As winds begin to peak this afternoon many of these locales in the direct lee will be hedging close to Moderate if we hit the 2” mark.  However, the Low definition stating “isolated terrain features” capture the developing pockets of instability fairly well.  Areas posted at Moderate yesterday continue to be labeled as such today due to the slabs already in place that we’ve been watching; and today’s new precipitation will effect the Sluice over to the Chute in Tuckerman more than other locations.  Upslope snow and a number of systems will give the higher summits a cloak of clouds and precipitation into the weekend.  Of course we’ll have to see how actual accumulations shake out, but don’t be surprised to see a mix of Moderate and Considerable danger ratings over the next few days.    

In addition to the development of avalanche conditions the other dominate hazard is the hard icy conditions that prevail in locations posted at Low.  Crampons, an ice ax and good self arrest skills are necessary for safe travel.  Many fall lines are peppered with rocks, brush and other unfortunate body stoppers so consider your travel routes well and think about who might fall above you this busy holiday week.   

Please Remember:

  • Safe travel in avalanche terrain requires training and experience. This advisory is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
  • Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast.
  • For more information contact the Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or the Harvard Cabin.  
  • Posted 8:25a.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
www.mountwashingtonavalanchecenter.org

2012-02-22 Print Version

 

Avalanche Advisory for Tuesday, 2-21-2012

Expires 12:00 midnight, February 21, 2012

Tuckerman Ravine has MODERATE and LOW avalanche danger.  The Sluice, Lip, Center Bowl, and Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lobster Claw, Right Gully, Left Gully, and Hillman’s Highway have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. The Lower Snowfields and the Little Headwall are not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

All forecast areas of Huntington Ravine have LOW avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

Stability is improving from day to day since the weekend snow stopped falling. Yesterday was a tough day to be in Tucks or up on Lion Head, due to almost constant blowing snow swirling around. The groups that did come out and braved the conditions seemed to be having a good time, with most of the traffic heading into Right Gully. Although there was a lot of snow being blown about, it didn’t build up into very reactive slabs. Rather, it would build to a critical point then release a small sluff down into lower angle terrain. This was going on everywhere from the Chute across to the Sluice. The dominant surface layer in these areas was a mixture of the sluffed-off snow and wind-effected snow. Digging pits was a futile exercise yesterday, since snow would fill them in just as quickly as I could shovel it out. But I was able to find the crust deeply buried with a light density layer above it, and above this is the aforementioned mixed surface layer. Overall depths of these layers is highly variable depending on your location. For example, where I dug in the Sluice the surface layer was about 70-80cm, the lighter layer was about 20cm thick, and the crust was 2cm. As mentioned, stability is getting better, but I don’t think it’s dropped enough that we can call any of the Moderate areas anything different today. Additionally, light winds may allow solar energy to rapidly warm the snowpack if clouds today do not materialize until later, which could lead to greater instability. Currently, the Sluice and Chute have lesser stability issues than the Lip and Center Bowl, but the degree of variability out there may put you into snow that is more unstable than anything I saw yesterday. As with yesterday, the areas of greatest concern are in the Lip and Center Bowl. If you trigger an avalanche today, it’s most likely to fail at the interface of the sluff/wind-effected layer and the lighter density slab below. There is generally good adhesion of the light density snow to the buried crust.

Huntington Ravine, Left Gully, and Hillman’s Highway all have similar conditions. You’ll find a lot of older surfaces. How do you know if it’s old? One key piece of evidence is a set of old bootprints that had the surrounding snow eroded out from around them. These things look like dinosaur spines from a distance, and they can be found in most of these forecast areas. Other than that, you’ll find strong stiff windslabs that make for good climbing conditions. You also might find areas of exposed old crust. This is likely to be found on S-facing slopes (such as below and near the top of Right Gully) and climbing it without crampons can be like trying to kick steps into a steel plate.

The brief sunny break in the weather will be coming to a close tonight. Some new snow is expected to fall overnight and into tomorrow, with unsettled and warm weather through the rest of the week. Keep your plans flexible and be sure to check the avalanche advisory before heading up into the ravines.

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 7:45am. 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

2012-02-21 Print Friendly

Avalanche Advisory for 2-20-2012

Expires 12:00 midnight, February 20, 2012

Tuckerman Ravine has MODERATE and LOW avalanche danger.  The Sluice, Lip, Center Bowl, and Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lobster Claw, Right Gully, Left Gully, and Hillman’s Highway have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. The Lower Snowfields and the Little Headwall are not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

All forecast areas of Huntington Ravine have LOW avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features.

It’s only fitting that on the Washington’s birthday holiday, the weather clears out and allows the mountain to show off a little bit. There are ample opportunities for recreating in Low avalanche danger today. All of Huntington is rated Low, and about half of our forecast areas of Tuckerman are as well. Surface conditions in these areas are mostly wind-scoured or strongly wind-effected. You could probably find an isolated pocket of unstable snow if you really wanted to, so don’t let your guard down 100% just yet. Although these areas are rated Low, it’s not the same kind of Low we typically get in the springtime melt-freeze cycles.

The recent 5.4” (13.7cm) of snow that has fallen on Mt. Washington over the past several days has loaded into lee aspects of Tuckerman. This includes an unexpected upslope event yesterday afternoon that brought another half inch of snow. Some of what we saw yesterday in the field showed us that there was a weak interface between layers of this new snow. We found this in Right Gully, the Sluice, the Chute, and down low under the Lip. We believe this is from changes in winds and snow crystal type during the snowfall on Saturday. Although the weak layer was present, in most areas where it was found, we didn’t find a strong tendency for propagation. I suspect this has changed for the worse overnight, due to the slight wind effect causing an increase in cohesiveness over time. The areas of most concern today are in the well-protected strong lee, such as underneath the Lip, under the ice in the Center Bowl, and just above the narrows on the climber’s right side of the Chute. Yesterday a group of climbers worked their way up the middle of the Sluice. Their tracks are gone today, indicating some loading did take place yesterday. On the whole, there is a range of stability within today’s Moderate rating. Your exact choice of route will determine whether you’re in the lower end of Moderate or venturing into the upper end of Moderate.

Yesterday three people were killed in an avalanche in Steven’s Pass, Washington. According to news reports, a total of 13 skiers were involved in the incident, four of these were carried a long distance. I mention this as a reminder that we all need to be mindful of what others are doing nearby us. Mt. Washington is a very busy place, especially this weekend. The psychological factors at work in backcountry recreation can be incredibly strong. Two things you should always remember here on Mt. Washington: 1) just because there is a bootpack established does not mean the slope is safe, and 2) whenever possible, exposing only one person at a time to avalanche hazard is a good idea. There’s a lot more to know than just these points, but remember these and your avalanche education will be off to a good start.

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 8:35am. 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

2012-02-20 Print Friendly

Avalanche Advisory for Sunday, 2-19-2012

Expires 12:00 midnight, February 19, 2012

Tuckerman Ravine has CONSIDERABLE and MODERATE avalanche danger.  The Sluice, Lip, Center Bowl, and Chute have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. Right Gully, Left Gully, and Hillman’s Highway have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. The Lobster Claw has Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. The Lower Snowfields and the Little Headwall are not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

Huntington Ravine has MODERATE and LOW avalanche danger.  North, Damnation, Pinnacle, Odell, and the Escape Hatch have Low avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. Yale, Central, and South gullies have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.

Five inches (13cm) of new snow in the past three days has done a lot to change the appearance of the ravines since the last time they were basking in sunlight on Thursday. What had been a mix of wind effected slabs, ski and boot tracks, and crusts is now covered in a smooth blanket of creamy white windslab. This is what winter up here is supposed to be like. The weather today is going to play a role in the avalanche danger rating. Currently winds are blowing from the NW at 55-65mph (89-105kph), and blowing snow is coming in from above the ravines. This active loading is preventing me from dropping the danger rating in the Sluice through the Chute in Tuckerman. More than a couple times, I’ve seen bluebird days just like this where low drifting snow into the Lip and Bowl is sufficient to trigger an avalanche. As high pressure builds in, winds will decrease in velocity. This may shut down wind loading altogether and eliminate the potential for naturally-triggered avalanches, which in turn would bring the avalanche danger down to Moderate. The snow that will be leftover will still be worthy of careful stability evaluation if you are looking to get out onto the slopes. This morning there are crown lines visible from recent avalanches in the Duchess and the Center Bowl. These should be considered “bulls-eye” data that indicate the presence of unstable snow. The crown in the Bowl has mostly reloaded and may not be visible for much longer if the wind loading persists. As with the past few days, the primary threat is the newly developed slabs from the recent snow.

Some areas of Tuckerman offer better options than others for traveling through avalanche terrain. Due to the low snow totals this season, the terrain on the northern side, i.e. Right Gully and Lobster Claw, has more discontinuous snowfields and more islands of safety that you can link together. Areas such as Hillman’s and Left Gully will make it more difficult to avoid exposure to the avalanche paths. Keep in mind there are lots of human factors at play today. It’s the first sunny day after a snowfall, it’s a holiday weekend, and the snow looks like it would be a joy to ski or ride…all these mean you’ll need to be heads up not only for yourself, but for what others are doing nearby.

Huntington has a mix of Low and Moderate danger. In those locations rated Low, expect to find small pockets of unstable new snow. Areas such as above the ice in Odell, near the top of Pinnacle, and in climbers’ right side of the Escape Hatch are examples of where you might find these. The locations rated Moderate have larger snowfields that are too big to call “pockets”. Whether the slab you encounter is small or large, you’ll want to evaluate the stability and do your best to avoid traveling through unstable snow. The consequences of even a very small slide in Huntington can be severe.     

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 8:35am. 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

2012-02-19 Print Friendly

Avalanche Advisory for Saturday 2-18-2012

Expires 12:00 midnight, February 18, 2012

Tuckerman Ravine has CONSIDERABLE and MODERATE avalanche danger.  The Sluice, Lip, Center Bowl, and Chute have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. Right Gully, Lobster Claw, 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 not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

Huntington Ravine has CONSIDERABLE and MODERATE avalanche danger.  Yale, Central, Pinnacle, Odell, and South gullies have Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are likely. North, Damnation, and the Escape Hatch have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.

If you’ve been spending your time down in the valleys over the past two days, you might be wondering why avalanche danger is where it is. After an uncomfortably cold morning in Tuckerman yesterday, I was shocked to drive down into sunny 40F temperatures in Gorham. The past couple of days have been very winter-like up here, and we’ve even received a couple shots of new snow. So far, the snow totals have been 3” at the summit, with another 1-2” forecasted for today. We estimate that roughly the same amount has fallen at lower elevations, but the winds have conspired to prevent us from accurately measuring this snowfall. This has all taken place since early Friday morning, and during this time winds have slowly ramped up from SW 15mph (24kph) to the current WNW 50-60mph range (80-97kph). Today we’ll have a little more snow this morning, followed by a brief break in the weather, and then another snow shower in the afternoon.

With the winds acting as they have been, we have concerns about the potential for both naturally triggered and human triggered avalanches. Both of these concerns are made worse today by the fact that it’s a Saturday on a holiday weekend, and visibility is incredibly poor. Don’t make the mistake of unknowingly being in an avalanche runout path, because you won’t have any indication of what’s going on above you. The areas that are most concerning are in the middle of both Tuckerman and Huntington Ravines. Going to the floor of Tuckerman to “take a look” or hiking around on the fan in Huntington will put you at risk of avalanches from above.

The snowpack prior to the new snow was generally stable in all aspects. South-facing slopes received strong solar gain on Thursday, causing the top layers to moisten and subsequently refreeze. East-facing and north-facing slopes didn’t get this new crust development, but there were some places with an older crust exposed at the surface. The northern gullies in Huntington and Lobster Claw and Right Gully will have the best travel options for avoiding newly deposited slabs, but you should expect any new slabs that did develop to be unstable as they are likely sitting on top of a slick 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 8:35am. 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

2012-02-18 Print Friendly

Avalanche Advisory for Friday, 2-17-2012

Expires 12:00 midnight, February 17, 2012

Tuckerman Ravine has CONSIDERABLE avalanche danger.  Naturally-triggered avalanches are possible and human-triggered avalanches are likely. The only exception to this is the Lobster Claw, which has Moderate avalanche danger. Naturally-triggered avalanches are unlikely and human-triggered avalanches are possible. The Lower Snowfields and the Little Headwall are not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

Huntington Ravine has CONSIDERABLE and MODERATE avalanche danger. Yale, Central, Pinnacle, and Odell have Considerable avalanche danger. Naturally-triggered avalanches are possible and human-triggered avalanches are likely. North, Damnation, South, and the Escape Hatch have Moderate avalanche danger. Naturally-triggered avalanches are unlikely and human-triggered avalanches are possible.

The most important thing we want you to understand today is that avalanche danger will be rising. The later you are out on the mountain, the more likely you are to encounter unstable snow. So far, Mt. Washington has received 1.2” (3cm) of 10% density snow, and it is currently snowing at Hermit Lake. We are expecting an additional 1-3” (2.5-7.5cm) during the day and more coming overnight. Winds are going to be at an ideal speed and direction for transporting the 2-4” of available snow into the ravines today, blowing from the W at 35-50mph (56-80kph) early and ramping up to NW 50-70mph (80-113kph) with higher gusts in the afternoon.

Prior to the onset of new snow last night, both ravines had good stability. We’d been at Low danger for at least a couple days in all forecast areas. Today, the primary threat will be windslabs developing from the new snow and wind combination. Expect areas with a strong easterly aspect to develop instabilities first, followed by the adjacent locations. At some point today, I expect to have naturally-triggered avalanches in Tuckerman. I don’t think it’s enough probability to warrant a High rating, but if I were betting on where avalanches will happen today, the Center Bowl and Lip area is where my money would go. I have little doubt these areas will reach into Considerable territory. Other adjacent areas will also get there, but they’ll take more time as the bed surfaces first need to get smoothed out by early wind loading. In Huntington a similar story is playing out, the strong easterly aspects will rise most quickly, followed by adjacent areas. Central, Pinnacle, and Odell stand out for me as the areas of most concern here. Yale and South won’t be far behind, either. Pay attention to the depth of the new snow in Huntington, and be thinking about what could be developing in the gully up above you.

The winds and the potential for new snow will continue to increase into the night, which will allow slab development to continue as well. At this point, I think it’s safe to say there will be some avalanche danger to contend with if you’re coming to the mountain tomorrow. As we do every Friday, we’ll post an update on the Weekend Update section of our website later this afternoon. Also check back for new photos from yesterday’s field trip to the summit.

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 8:35am. 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

2012-02-17 Print Friendly

Avalanche Advisory for Thursday, 2-16-2012

Expires 12:00 midnight, February 16, 2012

Tuckerman Ravine and Huntington Ravine have LOW avalanche danger. Natural and human triggered avalanches are unlikely except in isolated terrain features. The Lower Snowfields and Little Headwall are not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

This morning it is my pleasure to bring you a double dose of good news—or, more precisely, to reiterate the weather forecast put out this morning by our friends on the top of Mt. Washington and to give you more or less the same avalanche forecast that Chris wrote yesterday. Both of these are better than what you might be seeing if you’re looking at a weather forecast for the valleys or southern NH. Let’s get into the stability discussion first. Snow stability in the ravines is generally good. We did receive a dusting of snow since yesterday, but this came without much wind at all and will be insufficient to make any difference to avalanche conditions. Today you’ll have many options for different mountaineering routes around the mountain, so get out an enjoy them. Of course, you should still take proper precautions when traveling through avalanche terrain.

The other bit of good news comes to us from the Mt. Washington Observatory and the National Weather Service. Apparently there is going to be some snow in the mountains late today and overnight. Yeah, I couldn’t believe it when I read it for myself. Snow in February? Amazing. This highly unusual weather event is expected to deliver 2-4” (5-10cm) of snow to the higher terrain of the White Mountains. Ok, please excuse me if that’s too heavy handed with the sarcasm. After only 107 total inches (271cm) of snow since November 1 at the summit, of which only 11” has come in the last two weeks, I’m feeling less than optimistic about the prospects for the rest of the winter. Regardless of how I feel, there is snow coming tonight. This snow will come with winds from the SW shifting to the W and increasing in speeds. On Friday we’ll likely see some lingering upslope snow showers, hopefully accumulating to a couple more inches. Winds will continue to increase in velocity, setting us up for a holiday weekend with avalanche danger greater than where it stands today.

We’ve fielded a lot of questions recently about how conditions are coming along up here. It’s no secret that this has been a very dry winter, with a seemingly excessive number of warm days up high. The slopes of Tuckerman Ravine are snow covered, but there are still lots of exposed rocks and brush. The floor of the ravine has seen very few large avalanches, which is the primary way it fills in with snow. Most of the gullies have also had few avalanches, so their runouts are not very well filled in either. Getting onto the Little Headwall is a nasty bushwhack no matter which way you go about it. Despite the general lack of snow, conditions aren’t too bad. Keep in mind that surface conditions for travel can change greatly from day to day, as can the avalanche danger. One day might be “good” or even “great” conditions, but the following day might be “horrifying.”

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 8:00am. 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

2012-02-16 Print friendly

Avalanche Advisory for Wednesday 2-15-2012

Expires at midnight, Wednesday 2-15-2012

Tuckerman and Huntington Ravines have LOW avalanche danger.  Natural and human triggered avalanches are unlikely except in isolated terrain features. The Lower Snowfields and the Little Headwall are not posted due to an overall lack of snow. Forecasts for these locations will begin when conditions warrant.

 A foreboding sky over the mountains is a bit more bark than bite today as weather forecasts are only calling for some flurries and a potential brief snow shower.  A disorganized system will be shuffling along giving the mountains, clouds and fog across the higher landscape of the White’s through the day.  We aren’t anticipating enough snow to make a difference for snow stability to move any avalanche forecasts above ‘Low’.  As always be ready for the mountains to deliver some weather surprises, such as a shot of snow.  However, no weather information is pointing to getting more than a passing shower or two of light intensity.  As we move into tonight and tomorrow the chance of precipitation will increase.  Thursday night and Friday we have a 70% chance of moisture with the potential of 2-4” (5-10cm) to fall before a clearing weekend.  Overall, it will be a cloudy few days ahead with a bit of precipitation each day.  We are continuing to run the fine line between rain and snow due to temperature expectations near the freezing point at mid mountain elevations so stay tuned.

Expect foot travel to be a mixed bag of staying on top due to hard crusts and steel slab styrofoam, or breaking through the surface down in the trees or in protected lee areas that were protected from high winds earlier in the week.  As mentioned yesterday we are continuing to do some hauling on the Sherburne ski trail with our snowcat due to extremely thin coverage on the Tucks Trail.  Talking to two skiers yesterday the cat tracks are chewing up the ice which actually improved the rugged ski conditions.              

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. 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
www.mountwashingtonavalanchecenter.org

2012-02-15 Print Version