Avalanche Forecast Archives

2017 – 2018 Season

Avalanche Advisory for Tuesday, March 27, 2018

Date: March 27, 2018
A significant warm-up today will make loose wet sluffs the primary avalanche problem on sun exposed aspects. Loose dry sluffs are still possible on steep and shady aspects. We expect these small avalanches which could easily knock you off your feet to occur primarily in the few inches of snow which fell late Saturday and into Sunday. The small and isolated pockets of soft and thicker wind slab which formed from that recent snow could begin to act as a wet slab on south facing slopes and should be on your radar in all terrain. The older, widespread, and hard wind slab that is thinly covered in many areas by the newer snow has been unreactive to human and natural triggers and this trend will likely continue. That said, a significant warming like our sun-exposed slopes will experience today can awaken previously unreactive layers at or near the surface. It’s again a reason that “Low” does not mean “No” avalanche danger, and that travelling one at a time, with your beacon, probe, and shovel, is advisable.

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

Avalanche Advisory for Monday, March 26, 2018

Date: March 26, 2018
Limited wind transport of the several inches of snow which fell in the past 48 hours make loose dry sluffs our primary avalanche problem. Loose snow avalanches won’t bury you today but could knock you off your feet and are possible on most steep slopes. The new snow is distributed fairly evenly across our terrain, though a few areas saw wind scouring and the possibility for small, isolated pockets of wind slab does exist. A firm and generally smooth surface of older snow exists beneath the thin new snow. Conditions are generally edge-able and good for crampon and ice axe travel, but don’t expect to arrest a fall with any ease. A long sliding fall which could be caused by a loose dry sluff or just a stumble is likely your primary hazard to manage today.

Avalanche Advisory for Sunday, March 25, 2018

Date: March 25, 2018
Snow that arrived overnight has the potential to form wind slab and loose-dry avalanches. Another shot of snow this morning will exacerbate this problem. While wind speeds should remain mild by our standards, the recorded snow has a very light density, making wind transport possible on low wind speed. Wind speeds should increase slightly this morning to above 40mph. This has the potential to load snow into the northern gullies in both ravines as well as cross-load Moderate rated terrain. With the combination of snow density and wind speeds, expect wind slab to be touchy to a human trigger, particularly with the firm bed surface it will reside on. While northern gullies in Huntington are more in the direct lee of today’s wind, a smaller fetch and confined, steep terrain will make loose dry sluffing more of a an issue. If an avalanche occurs, it is likely to be small, but potentially enough to swipe your feet out from underneath you and lead to a long, sliding fall. As the bed surface in all avalanche terrain is firm, arresting a fall today will be difficult.

Avalanche Advisory for Saturday, March 24, 2018

Date: March 24, 2018
High temperatures in the low teen’s F, very firm snow surfaces and summit fog may have skiers dreaming about days of elevated avalanche danger today. Though climbers will appreciate the ease of climbing on the firm surface, skiers will be dealing with hard, fast conditions with no chance for softening snow. Light snow showers on light NW winds early this morning have created the illusion of fresh snow but don’t be fooled by the dust on crust effect. More snow showers today may create pockets of wind slab that will serve only to exacerbate the long sliding fall concern. For these reasons, expect low avalanche danger in all forecast areas due to new wind slabs this afternoon. Ice climbers should be aware that a climber fell up to their waist in the icy water behind an ice dam in Odell Gully yesterday. Expect the potential for an ice dam rupture to exist for a while on all ice climbs as spring continues and temperatures swing around the freezing point. Large chunks of ice are also beginning to appear on the floor of both Ravines.

Avalanche Advisory for Friday, March 23, 2018

Date: March 23, 2018
Wind slab is the avalanche problem today. It is unlikely that a human could trigger the current wind slab in our terrain due to its firm and supportive nature. As the slab itself has a high degree of tensile strength, an avalanche would be large, giving travelers in avalanche terrain a classic low probability, high consequence situation. Small areas of softer slab exist that are providing the isolated pockets of less stable snow. The surface of our snowpack is largely smooth, providing quality skiing, but also the ideal surface for a long, sliding fall. Losing a ski edge or catching a crampon point in steep terrain today will likely have dire consequences. With the possibility of 1” of snow today, dry loose sluffing in extreme terrain should be on your radar as wind speeds are forecast to be on the low side.

Avalanche Advisory for Thursday, March 22, 2018

Date: March 22, 2018
A low pressure system passing to our south and east may generate 2” of snow today on the mountain. This snow will fall on N and NE winds and may build and cross-load small wind slabs in sheltered locations, particularly northern gullies in Huntington and the right side of Tuckerman Ravine. Any wind slabs that build will be on a very firm, and in most places, smooth snowpack. The hard snow surface will increase the likelihood of triggering a small wind slab and raise the consequences if you were to be surprised or swept off of your feet. If you are playing in steep terrain, an ice axe and crampons will make you feel a lot more secure due to the hard and just barely edge-able snow. Though wind slab may be the primary avalanche problem, a long sliding fall is a close second on the list of hazards.  

Avalanche Advisory for Wednesday, March 21, 2018

Date: March 21, 2018
Successive storms late last week built an upper snowpack of layered wind slabs on an old melt/freeze crust. These generally firm slabs are gaining stability and becoming unreactive, though isolated pockets that you could still trigger do exist. It’s worth considering that wind slab is a spatially variable avalanche problem by nature as you choose and move through terrain today. Our snow surface is a mix of smooth and wind textured firm wind slab with the scattered pockets of softer slab that pose a greater stability concern, and is providing enjoyable conditions for skiers and climbers alike. This morning looks to provide a continued nice weather window to enjoy the mountain before clouds and wind increase later today.

Avalanche Advisory for Tuesday, March 20, 2018

Date: March 20, 2018
Wind slab which varies in size and character across the terrain remains our primary avalanche problem. Present in all forecast areas and largest in Moderate rated areas, these slabs should be stubborn to a human trigger but could result in a large avalanche. Cold temperatures which slow bonding between recently formed layers lead us to believe that human triggered avalanches are still possible today, though natural avalanches will be unlikely. Surface snow is fairly firm and supportable in many areas, but softer pockets can be found as well. This spatial variability necessitates careful evaluation of the avalanche problem on your specific route, and that travelling one at a time on and below all avalanche terrain remains appropriate. “Low” avalanche danger does not mean “no” avalanche danger!

Avalanche Advisory for Monday, March 19, 2018

Date: March 19, 2018
Wind slab remains our primary avalanche problem today. Generally firm and relatively stubborn to a human trigger, these recently formed surface layers are of most concern in Moderate rated areas where they are particularly large, potentially well-connected, and smooth on the surface. These surface slabs are layered over others formed in the past week, and while we’re not overly concerned with an avalanche initiating deep in the snowpack, it’s worth considering that an avalanche today could ultimately entrain a great deal of snow. It’s a low probability/ high consequence kind of day, with your likelihood of triggering an avalanche not exceeding “possible”. Travelling one at a time through and below avalanche terrain, from safe zone to safe zone, remains a wise and relevant practice on days like today.

Avalanche Advisory for Sunday, March 18, 2018

Date: March 18, 2018
Areas of visibly smooth wind slab are our primary avalanche problem today. Moderate rated terrain holds the largest and most continuous of these newly formed slabs which primarily exist in the lower half of our forecast areas. Expect these slabs to be stubborn to touchy though fairly hard, making human triggered avalanches possible and natural avalanches unlikely. The mostly wind textured snow dominant in the rest of our terrain is certainly harder still. It’s important to always remember that “Low” avalanche danger does not mean “No” avalanche danger as pockets of more reactive and softer snow can be found in Low rated terrain. Visibility should facilitate your ability to choose safer travel options, but remember that the cold temperatures and strong wind would elevate the consequences of any accident today.

Avalanche Advisory for Saturday, March 17, 2018

Date: March 17, 2018
Our avalanche forecast today is driven by the legendary, howling winds that hammer Mount Washington. Strong winds overnight and this morning have scoured much of our terrain but have also left firm and stubborn wind slabs in their wake. These wind slabs are the primary avalanche problem today. The moderate rated terrain in the headwall area of Tuckerman Ravine harbors the largest wind slabs with pockets of wind slab elsewhere. In low rated areas these slabs will generally be on the smaller side and should be pretty easily avoidable, though it will require good micro-route finding skills. Though these firm wind slabs will be the primary avalanche problem, the main environmental challenge you’ll face today is cold temps and wind chill. You’ll need the luck o’ the Irish to avoid frost nip if you venture above treeline today.  

Avalanche Advisory for Friday, March 16, 2018

Date: March 16, 2018
Strong NW wind created thick wind slabs yesterday. These will be found in greatest concentration in Considerable rated areas. While human-triggered avalanches are more likely than natural avalanches, wind slabs have the potential to run far today. A mix of cross-loading and scouring has taken place on other slopes. Pay close attention to this interplay as it may be easiest to trigger this wind slab on its outer edges. The boundary of wind slab and old surface may be blurry due to newer snow over the old ice crust. Slopes with a Moderate rating today, particularly Central Gully in Huntington, should not be taken lightly. Areas of more reactive snow will likely be found in the most sheltered areas and should be negotiated appropriately. Old icy surface or older firm wind slabs may be found in areas and will make great climbing, but also provide the potential for sliding falls. An ice axe and crampons will be useful in steep terrain today.

Avalanche Advisory for Thursday, March 15, 2018

Date: March 15, 2018
An increase in wind speed and a shift in wind direction will keep avalanche danger elevated today. Recent snowfall will be carried by NW winds and build wind slabs in many areas. Natural wind slab avalanches are possible in bigger terrain such as the Lip, Center Bowl, Chute and Hillman’s Highway in Tuckerman Ravine and Central Gully in Huntington. Dry loose avalanches are likely in the steepest areas of both Ravines and will contribute to the likelihood of human triggered avalanches on the approach to steep pitches of ice or rock. Wind slabs should become firm and stubborn with anticipated wind speeds but not before becoming unstable as they build. Staying on low angle terrain, avoiding runouts and traveling one at a time while making careful snowpack assessments will be critical today if you choose to venture into avalanche terrain. Precious little of this low angle terrain exists in our forecast zones, so seeking out lower elevation, less wind effected terrain may be your best bet until wind subsides and visibility improves.  

Avalanche Advisory for Wednesday, March 14, 2018

Date: March 14, 2018
Wind slab formed from northerly wind will be the primary avalanche problem this morning before wind shifts NW and begins to build new and potentially larger slabs late today. These new layers will all be very sensitive, likely to avalanche naturally and very likely to be human triggered in High rated areas. If that’s not enough to keep you out of the terrain, storm slabs and dry loose sluffing will be secondary problems forming from the snow currently falling on light wind. This number of avalanche problems is compounded by deeper and potentially unstable slabs formed late last week in much of the terrain. You’re likely to trigger an avalanche in essentially all forecast areas today, and avalanches could be quite large. It’s a great day to enjoy the powder away from avalanche terrain or at the ski area!

Avalanche Advisory for Tuesday, March 13, 2018

Date: March 13, 2018
Our primary avalanche problem will be very sensitive wind slab developing from today’s storm with instability peaking late today. East winds will shift N as snowfall intensity increases through the day. We expect greatest loading in High rated areas. Natural avalanches are likely and human triggered avalanches are very likely in these areas, and all would be large. Considerable areas are rated as such for two distinct reasons. We expect to see less loading in more windward terrain like Chute, Left, and Hillman’s Highway in Tuckerman and Odell, South, and Escape Hatch in Huntington. Alternately, Lobster Claw and Right Gully in Tuckerman as well as North, Damnation, and Yale in Huntington will receive direct wind loading but aren’t capable of producing a truly large avalanche due to less existing snow in avalanche start zones. A secondary avalanche problem today is older but still touchy wind slabs which exist in most of our terrain. These layers are a concern this morning, prior to new slab development, and could also provide step-down potential for avalanches late today. Avoiding these avalanche problems will be difficult to impossible today. Remember that the relatively smaller human triggered avalanches likely in Considerable rated areas can still have fatal consequences.

Avalanche Advisory for Monday, March 12, 2018

Date: March 12, 2018
Wind slab formed in the past two days covers most of our terrain and is our primary avalanche problem. These smooth surface wind slabs were formed by W to NW wind which either directly loaded or cross loaded most forecast areas. In many areas, this somewhat soft but cohesive surface snow overlies slabs formed late last week that are similar if a little less soft in character. We expect all smooth surface snow to be sensitive to a human trigger today. The connected and consistent nature of wind slab means that such avalanches could be quite large. Upper portions of Left Gully and most of Odell have heavily wind textured snow at the surface that will be fairly hard and more stubborn to a human trigger, hence their Moderate rating. One if not two natural avalanches in Lobster Claw yesterday have reduced snow available to avalanche, though sensitive pockets likely still exist. Moderate avalanche danger means that human triggered avalanches are possible, suggesting that you should evaluate snow and terrain carefully prior to committing to a slope. It’s not likely you’ll be able to avoid the avalanche problem in Moderate rated terrain today. It’s a beautiful day to enjoy the mountains, so carefully evaluate all snow and terrain. Choose to come home safely.

Avalanche Advisory for Wednesday, February 28, 2018

Date: February 28, 2018
Wet weather today may reduce stability in wind slabs formed earlier in the week, making wet slab our primary avalanche problem today. This problem is isolated to areas of existing wind slab which can be visually distinguished from the hard, refrozen snow also present at the surface. Timing of peak instability depends directly on the type and timing of precipitation in our terrain. Watch for precipitation falling predominantly as rain to result in the greatest potential for unstable snow. If we receive less rain and more frozen precipitation particles, expect lesser instability of existing slabs. Bear in mind that significant portions of our terrain have firm, slick, refrozen snow at the surface. The risk of a long sliding fall that would be near impossible to arrest may be of greater concern than an avalanche today. Also remember that “Low” avalanche danger does not mean “No” avalanche danger.

Avalanche Advisory for Tuesday, February 27, 2018

Date: February 27, 2018
Areas of wind slab exist across much of our terrain amid a more widespread refrozen surface of older snow. Size of this wind slab varies across Moderate-rated terrain and is distributed most widely in Central Gully in Huntington and Hillman’s Highway in Tuckerman. Today provides both an obvious and challenging avalanche problem to deal with for those seeking good turns. The new slab in which it is possible for you to trigger an avalanche is easy to see, appearing very white in contrast with the grey old surface. You can avoid the avalanche problem by avoiding travel on or below this visually apparent wind slab. That said, searching for good turns will lead you to travel on the avalanche problem, as the refrozen old surface will be far less than ideal for skiers and riders. Climbers will find good crampon purchase on the refrozen surface and likely be less tempted to travel on wind slab. This slick refrozen surface will easily allow a long sliding fall that most would struggle to arrest. If a stumble or even the smallest of avalanches causes you to lose your footing, you could take a long high-speed slide with potentially serious consequences. Take care, avoid falls and carefully assess consequence when choosing terrain.

Avalanche Advisory for Monday, February 26, 2018

Date: February 26, 2018
Today’s avalanche problem is wind slab. This hazard will increase slowly through the day as wind continues to transport snow from the fetch into avalanche terrain. Areas of largest concern are those in the direct lee of W and NW wind as those will see the most loading today. Also of concern would be gullies that were in the lee of yesterday’s S and SE wind. Areas rated Moderate today had less developed bed-surfaces prior to yesterday.

Avalanche Advisory for Sunday, February 25, 2018

Date: February 25, 2018
All forecast areas this morning are icy and firm with low avalanche hazard. Incoming precipitation will create a widespread wind slab avalanche problem throughout our forecast terrain and increase our avalanche danger to Considerable as the day progresses. The size and tendency of avalanches to release naturally will largely depend on the amount of snow that falls this afternoon. The forecast snowfall of four to six inches of snow in the higher terrain is plenty of snow to create slabs that are capable of knocking you off your feet and carrying you down slope. Combined with an icy bed surface on our steep 35-50-degree terrain, even a small avalanche today can have serious consequences. While winds from the south might seem to target only north facing terrain for wind loading, count on cross-loading and sluffing to load east facing slopes in a similar fashion. If the steep icy base and wind loading aren’t enough of a challenge today, remember that this precipitation will be warming and becoming increasingly dense. This will create an “upside down” snowpack that may begin to act like a wet slab, making the new snow more sensitive to a human-trigger.

Avalanche Advisory for Saturday, February 24, 2018

Date: February 24, 2018
The mixed bag of precipitation late yesterday and overnight largely fell as rain, freezing rain, and sleet, all of which refroze and now contribute to our hard and icy snow surface. The limited new snow mixed in this storm was heavily transported by wind, and at best amounted to quite small wind slabs that pose little danger to travelers in the alpine. Potential for a long sliding fall on our largely hard and slick snow surface should guide your terrain choices today. Realize that preventing such a fall is essential, as arresting one would be very difficult. Crampons, ice axes, and your ability to use them are essential on snow slopes. Clear skies and sun may briefly and slightly soften snow on south-facing aspects this afternoon, but this window of anything but rock-hard snow will be brief if it happens at all.

Avalanche Advisory for Friday, February 23, 2018

Date: February 23, 2018
This morning, there is no avalanche problem. Avalanche terrain consists of refrozen snow that with its hard, icy surface, will require the use of crampons and an ice axe to navigate safely. Long sliding falls are currently the greatest danger. Up to 2” of snow is forecast on increasing SW wind in the afternoon and will create areas of wind slab. If we receive the upper end of the forecast snow total, areas in the lee of SW and W wind may exceed the current Low rating.  Be aware of this in Hillman’s Highway, Left Gully and the Chute in Tuckerman as well as Escape Hatch, South and Odell in Huntington. Warming temperatures late may mix sleet and freezing rain into this snow, adding a wet layer to the snow surface. Travelers out late in the day should keep an eye on the sky and be prepared to re-evaluate plans if we receive the upper end of forecast totals.

Avalanche Advisory for Thursday, February 22, 2018

Date: February 22, 2018
Huntington and Tuckerman Ravines have LOW avalanche danger. All forecast areas have Low avalanche danger. Generally safe avalanche conditions exist. The Little Headwall is not rated and is once again an open waterfall with very little snow coverage remaining. AVALANCHE PROBLEM: Avalanche concerns today have been erased by the record setting warmth and rain over […]

Avalanche Advisory for Wednesday, February 21, 2018

Date: February 21, 2018
Our primary problem will be in the form of the skier or rider initiated loose wet avalanches which are trending towards likely today. Loose Wet avalanches which will be possible for a skier or snowboarder to initiate in steep terrain are our primary avalanche problem. Moderate rated areas held more soft snow at the surface prior to the current warm and wet weather and will be capable of producing large loose wet sluff and point release avalanches. While such avalanches would likely not bury you without a significant terrain trap, they can easily cause a fall and even carry you downhill. Realize that the steep terrain where loose wet activity is most likely to occur is also a particularly high consequence place to take a fall.

 If you venture into the terrain today, be aware that the record warmth is awakening a number of our typical spring hazards. Water flowing beneath the snow surface is creating areas of undermined snow that you could easily break through. Overhead hazards including icefall and to a lesser extent rockfall should be respected. When choosing terrain today, remember that these avoidable hazards have resulted in many accidents, some of them fatal. Don’t neglect to look at safer and equally rewarding options.

Avalanche Advisory for Tuesday, February 20, 2018

Date: February 20, 2018
Wet Slab is our primary avalanche problem with small slabs in many areas and large slabs in specific areas decreasing in stability through the day. Rain and melt water should wet recently formed wind slabs and percolate to the robust crust beneath them, lubricating this bed surface for avalanches to run on. Moderate rated areas hold significantly less new wind slab and are instead dominated by an old melt/freeze crust snow surface that is again melting. Wet slab avalanches are unlikely in anything but the recently formed wind slab. Peak instability of wet slabs is difficult to predict, but we expect human triggered avalanches to become likely and natural avalanches possible at some point later today. Wet Loose avalanches will be a rising concern as well today and could occur in much of our terrain. If in our terrain today, be on the lookout for overhead hazards in the form of icefall, rockfall, and of course the wet slab avalanches mentioned above. Also watch for weak snow undermined by water running beneath it which you could break through.

Avalanche Advisory for Monday, February 19, 2018

Date: February 19, 2018
Wind slab that formed over the weekend sits on a firm bed surface that has gone through multiple melt-freeze cycles. Yesterday’s 5” of snow fell on increasing wind speeds, creating large areas of wind slab. Wind speeds were at times strong enough to scour areas down to the icy bed surface, though these tend to be in lower portions of our terrain and present themselves with the appearance of gray snow or may even have a reflective sheen with today’s sun. Areas with a northerly and southerly exposure have the most scouring down low and contain firm-looking sastrugi up high, including Damnation and North in Huntington as well as the looker’s left fork of Hillman’s Highway. Places of most concern today will be the Sluice through Chute in Tuckerman and Central and Pinnacle in Huntington. Smooth wind slab dominates these areas and has covered rocks and old crown lines that were visible on Friday, giving an indication to the amount of loading that took place yesterday. Current blowing snow on SW wind of 45 mph is a sign that wind transport has not ended and our fetch still has transportable snow. SW shifting W wind today will allow areas of wind slab to grow in size today. While many gullies have old surface down low due to wind scouring, mid-elevations contain the largest smooth-looking wind slab that could prove touchy to human-triggers today.

Avalanche Advisory for Sunday, February 18, 2018

Date: February 18, 2018
Wind Slabs that will continue to develop through the day are our primary avalanche problem. Avalanche danger will increase through this afternoon as wind builds our several inches of new snow into much thicker slabs. Increasing wind speeds mean than snow deposited will be generally more dense over less dense snow and therefore be increasingly sensitive to a trigger. Natural avalanches will be possible and human triggered avalanches will be likely. Dry loose sluffs which could knock you off your feet, initiated naturally or by a human, should also be on your radar in our steep terrain. We still have relatively thin snow coverage in much of our terrain, particularly Huntington Ravine. This means that many hazards in the runout of our avalanche paths elevate the consequences of even a small avalanche. Consider the rocks, vegetation, and terrain traps which may be below you if you choose to travel in avalanche terrain today. Also remember that though avalanches typically occur on slopes steeper than 30 degrees, they can run well into flat areas like the floor of Tuckerman Ravine.

Avalanche Advisory for Saturday, February 17, 2018

Date: February 17, 2018
Huntington Ravine has MODERATE and LOW avalanche danger. Central and Pinnacle Gullies have Moderate avalanche danger. Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully to identify features of concern. All other forecast areas have Low avalanche danger. Watch for unstable snow on isolated terrain features. Tuckerman Ravine has MODERATE and LOW […]

Avalanche Advisory for Friday, February 16, 2018

Date: February 16, 2018
Huntington and Tuckerman Ravine have LOW avalanche danger. All forecast areas have Low avalanche danger. Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. AVALANCHE PROBLEM: The warm spell yesterday and last night brought another period of settlement and melt. The snowpack has already been through above freezing temperatures earlier in the […]

Avalanche Advisory for Thursday, February 15, 2018

Date: February 15, 2018
Huntington Ravine and Tuckerman Ravines have LOW avalanche danger. Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. AVALANCHE PROBLEM: No significant avalanche problem exists today as our dry spell continues. Surface snow consists of refrozen rain soaked crust which is hard and strong enough to not only support your weight but […]