Such powerful winds may come from a major storm that inundates the entire region, or result from an isolated event like an approaching thunderstorm or freak tornado. The result is the same. Trees are ripped up from their roots (known as tip-ups or blow-downs) or their trunks shatter (a snap). As they crash to the forest floor, a gap opens up overhead.

“Once the canopy becomes broken, the wind will eddy, swirl, and penetrate the gap from different directions,” Cogbill explains. “That is really disruptive.” In lower-elevation hardwood forests, the hole tends to slowly expand until a new generation of saplings plugs the gap. But at higher elevations in stands of balsam fir, it never goes away. Instead it slowly migrates, a phenomenon known as a fir wave.

Fir waves occur in only a handful of places worldwide—the mountains of Japan, the Newfoundland coast—but they are a pre-dominant feature in the Northeast above 3,000 feet. They begin when a stand of pure balsam fir is breached, exposing one of its edges. A fir tree can withstand extremely harsh conditions when surrounded by its protective kin, but without this shelter it rap-idly succumbs. This then exposes its immediate neighbors to the elements, which perish in turn. Over time, this line of mortality slowly progresses, a narrow swath of bleached snags and bushy sap-lings that trace up a mountainside like gray eyebrows. “As a gross average, fir waves are spaced about 60 meters apart and move about a meter a year,” Cogbill recounts. “Which means that the average longevity of these trees is only about 60 years.”

As you go higher up the mountainside, winds tend to increase in velocity. Average temperatures drop and the growing season shortens. In winter, ice forms on the trees, adding weight and stress in an already stressful environment. At a certain point, Cog-bill notes, “trees are de-leaved, then de-branched, then de-barked, then ground up in a blender.” And nowhere does that blender turn faster than atop 6,288-foot Mount Washington, the highest point in the Northeast.

Dense fog hurtles by me at roaring speed as I stand upon the uppermost turret of the Mount Washington Observatory one blustery March afternoon. Begoggled and fully encased in protective clothing, I face directly into the wind. Its jet engine roar deafens my ears. I tilt forward, adjusting my hands like miniature sails to remain upright. My jacket flaps violently. The very flesh of my arms seems to flap along with it.

I’ve come to the summit for an overnight visit to taste the power of extreme wind. Before we headed up the mountain, Observatory Director Peter Crane provided a synopsis of the coming experience. “It’s like being tackled by a cornerback—except that he’s invisible. It can be disconcerting, even scary.”

The wind is strong today—between 50 and 60 mph—yet it is only a few ticks above average for a winter day here. During the winter, summit wind speeds average 44 mph. Hurricane force occurs when the wind reaches 73 mph—and the top of Mount Washington meets or exceeds that 110 days a year, cracking 100 mph 63 days a year.

Later that day, we sit comfortably indoors as Dave Thurlow, one of the trip leaders, discusses the phenomena that cause such extreme winds. “The jet stream is at 35 to 40 thousand feet, which essentially creates a cap to the atmosphere. As approaching winds reach Mount Washington, they are com-pressed between this upper limit and the mountaintop. Conservation of momentum requires that the wind accelerate.” It’s similar to what happens when you put your thumb over a garden hose.

There are also other factors at play, Thurlow continues. “Mount Washington is situated in a generally windier place. It borders between the oceans and the continent, where there is more weather and more large-scale storms. And here at the mid-latitudes is where cold and warm, and dry and wet, air masses meet. I think of this as the meteorological coast. North America is to the north. South and east is the Atlantic Ocean. There are more chances to create more winds.”

Later that night I sit with Jon Cotton in the observatory’s main instrument room, where computer read-outs and wind measurement charts line the walls. Irish jig music plays in the background as the young tousle-haired observer reflects on his experiences with much higher wind speeds.

“Above 100 mph is when it gets interesting,” Cotton remarks. “Wind turbines would be destroyed. Cement tiles blow away. People have had eyeglass lenses blown out. It’s hard to breathe. You have to gulp for air. You get knocked around. It’s amazing. It really gets your adrenalin pumping.”

Thurlow adds his own experiences. “Once it gets over 120 mph, it’s impossible to do much of anything. I’ve been on the turret in 148 mph gusts. It was knocking me around so much that it was difficult to even grab the railings. The wind would blow my hand away.”

The next morning I stumble outside and into a blustery ice-encrusted world. The wind still whips and temperatures have dropped below the freezing point. The dense fog remains, but now the tiny airborne water drop-lets are solidifying to form thick feathers of rime ice, which grow into the wind from every available surface. The surrounding landscape is crusted white, a battered and desolate moonscape.

Far from the cobbled shoreline where I started my journey, the land scrapes high into the atmosphere and the air scours the earth to its rocky bones. The wind is at its strongest here at the top of its scale. I stare down at my jacket and watch as ice forms on its surface in a matter of minutes, a parting touch of wind’s power before we return to the calmer elevations below.

Matt Heid is a contributing editor for AMC Outdoors.

PREVIOUS PAGE

1 | 2 | 3