Let me start by stating two things: first, I’m not a meteorologist. Second, there’s a good reason why both the Observatory and NWS only forecast for 36 hours at a time for the higher summits. Too many variables are at play to change things and it’s hard to be accurate for longer than this. But we’re moving into a holiday weekend and it’s the start of the vacation week, so I’ll do my best at looking forward through Monday’s weather.
Temperatures: they’re quite warm at Pinkham right now (40F at 3pm), but we’ll start to see it cool off tonight. The trend will continue right through Monday, when it will be sub-zero on the summit, compared to 18F at this time Friday afternoon.
Winds: they will diminish through Saturday night, then begin to rise. Sunday night into Monday morning would expect winds to be howling loud enough to make Mt. Washington proud. Currently the GFS and NAM computer models are forecasting sustained NW winds around 100mph overnight on Sunday and into Monday.
Snow: I wish I could offer better news, but there isn’t much more than scattered showers in the forecast for Saturday. We may see a couple inches or more on Sunday. This new snow will load into the ravines on the strong NW winds. Long term we’re going to need some significant snowfall to have much chance at a sustained spring ski season.
And speaking of snow…as for avalanche conditions, assuming we’re going to be getting a few inches and strong W or NW winds on Sunday, it appears as though Saturday will be your best bet for getting out into steep terrain. Our last snows were on Monday and Tuesday, when about 5.5” fell across the higher terrain. Check out the advisories from the past week to get more details, but the short story is that this snow blew in after the big nor’easter, and most of our stability concerns are coming from this snow, not from what fell last Friday and Saturday.
In places, you can find deep wind-transported snow with numerous layers to it. One example is the approach to Central Gully. One person told us today that he turned back due to chest deep postholing. Now don’t get too excited over the idea of skiing chest deep snow. Spatial variability being the norm, I don’t think you’ll find large expanses of that snow that deep. Other locations hold harder windslabs; some other locations are scoured clean to the rain crust from late January. As if that’s not enough variability, in some places such as the top of Right Gully and Lobster Claw, you’ll find sun crusts, wind-sculpted features, and unsupportable facets sitting under the brush that is barely covered by snow, if at all. If you venture off the beaten path, you may find very difficult postholing conditions.
Looking for good news? Well, one way to look at it positively is that since we haven’t had snow since Tuesday, the slabs that are in place have been there for a few days. Temperatures have been mild, as well. Time and somewhat warm temperatures can often stabilize even a mid-winter snowpack. This isn’t to say that avalanche danger goes away completely, but the snow does become stronger.
To be honest with you, I’m surprised that no one has laid tracks down the Lip in the last few days. I looked at it on my day off on Wednesday, and decided to pass (Right Gully and Lobster Claw instead). It did look like really good riding. The reason for not riding it is simple…the consequences are just too much to justify the risk. With the general lack of snow in the bowl, an avalanche in the Lip would send you on a bumpy ride down over lots of rocks and ice cliffs, and into a terrain trap where the likelihood of a deep burial would increase. If you remember from your avalanche course, rocks, cliffs, and deep burials all contribute to much lower chances of survival. So if it’s that bad, why would I be surprised that it’s been left untouched? Well, after working in the ravine for ten years or so, I have become fairly skeptical of people’s ability to objectively assess and mitigate avalanche hazard. Once in a while we do see individuals with the skill and experience to make good informed decisions. That’s a rare treat for us!
What’s more common is the lure of good turns is so strong that it makes people essentially blinded to a lot of rather obvious information. This is more so the case on a generally bad snow year when good skiing and riding is harder to find. Even for intelligent, educated people, this attraction is hard to resist. It’s a part of the human condition; our brains are hard-wired to take shortcuts instead of deliberately making decisions. But that’s not a good excuse, because we can always stop and think about it a little more deliberately. So before you drop into the Lip this weekend, do me a favor and think about the snowpack, then think about your family, your friends, and how you’d rather end the day having a cold beer with them instead of a taking a ride in an ambulance or hearse. There’s no one in particular who I’ve seen in the last few days that makes me think about this, instead, I think I’m anticipating what will happen tomorrow.
Now, before I go…it’s a holiday weekend, which means that a lot of people are going to be out in the mountains. In avalanche terrain, this means a lot of potential triggers possibly moving around above you, or other innocent (ignorant?) people venturing into a runout path below you. If you’re ice climbing, this means there may be parties above you in the gullies dropping ice, carabiners, or who knows what. If you venture into Damnation, for example, you will be climbing underneath a very large overhanging cornice, perhaps 8’ tall and 30’ long. Should someone go wandering onto the top and break it off while you’re anywhere in the gully, the best you can do is hope it misses you. Mountain hazards always exist, however, it’s human interaction with hazard that causes accidents and injuries. When you have a higher concentration of people in a hazardous area, the probability of an incident rises as well. Pay attention to your surroundings and don’t be afraid to alter your plans based on what is going on around you.
See you on the hill this weekend,
Ps: In case you hadn’t noticed, we started a new area of our webpage, “The Pit.” Take a look at it every so often. It’ll be the place where we can dish out information that isn’t worthy of the advisory but we want you to know about. One of the next posts I’ll be working on…the 2013 State of the Ravine. I’ll give a summary of the season so far, and prognosticate about how the late season may play out. Stay tuned in the coming days to the Pit.
This advisory expires at 12:00 midnight, Friday 2-15-2013
Tuckerman Ravine has LOW and MODERATE avalanche danger. Lobster Claw, Right Gully, Left Gully, Hillman’s Highway, Lower Snowfields, and the Little Headwall have Low avalanche danger. Natural and human triggered avalanches are unlikely. Sluice, Lip, Center Bowl, and Chute have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.
Huntington Ravine has LOW and MODERATE avalanche danger. North, Damnation, Yale, South, and Escape Hatch have Low avalanche danger. Natural and human triggered avalanches are unlikely. Central, Pinnacle, and Odell have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.
Though less than ideal weather conditions exist today for skiing, generally good stability could yield nice skiing and riding in Tuckerman Ravine today for those willing to lower their standards a bit. Our snowpack is still shallow for this time of year so lots of ice is showing in the headwall and Sluice and lots of bushes will limit you to short radius turns in Lobster Claw, Right and lower in Left Gully. Safe travel techniques when skiing will be challenging due to limited visibility, due to fog and a trace to 2″ (5cm) of new snow coming and may necessitate short pitches of skiing in order to maintain “eyes on” your partner. Climbers will find lots of ice trending to the “fatter” side in Huntington Ravine gullies.
Pockets of pooled, heavily rimed snow crystals are the areas of concern in both ravines today. Though not widespread, you will find areas of windslab on top of the weak rimed interface that are reactive to a moderate to hard trigger. If you stumble into a larger, deeper area of this slab, you could trigger a consequential avalanche. Yesterday, Chris and I observed several reactive layers, varying in depth from 6″-12″ (15-30cm), created by changes in snow density. These weak interfaces are probably deeper, perhaps significantly, in places. Stay tuned in to the qualities of the upper layer(s) of snow and be alert to changing cohesion and reactivity of the slab. Cracks shooting out more than a foot or so are a warning sign to remind you to manage the hazard by either tweaking your route to avoid the slab or finding and placing pro.
Boot penetration averages around 25 cm with deeper postholing in the faceted areas around rocks and bushes. Additionally, old rain crust is showing in spots and harder windboard exists in others. There was strong solar gain in the upper 4″ (10cm) of the snow on steep south facing terrain that moistened the snow and helped the stability process but created a bit of sun crust today. Be sure to check our Weekend Update later today or this evening for more information about the busy upcoming holiday weekend.
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. Friday 2-15-2013. A new advisory will be issued tomorrow.
Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856