“STOP. The area ahead has the worst weather in
So read the signs on the edge of the alpine zone in
Since 1932, the Mt. Washington Observatory has explored this question by monitoring the weather and conducting research atop its lonely perch at 6,288 feet. In the words of Scott Henley, the Executive Director of the Observatory, the place attracts “a certain kind of person… avid outdoorsmen and women. It’s a grueling job because you’re marooned up there.” The staff on
I talked to Jon Cotton, the night Observer, late one night after he finished one of his hourly forays to check the instruments. Most of the measurements must be taken manually because the weather tends to disrupt electronics.
Cotton, 26, has been working at the Observatory in various capacities since 2003. A native of New Hampshire, he worked seven seasons as a hutman for the Appalachian Mountain Club and found that the Observatory, in addition to allowing him to pursue his twin passions for computer science and the outdoors, filled out his seasonal schedule.
Cotton identifies three main hazards that Observers look out for when going outside to monitor their instruments. Lightning, extreme winds, and severe white out conditions are all excellent grounds for staying indoors. “You get used to what you can take,” he says, and adds that as the staff knows exactly where to find their instruments and do not have to walk far, getting lost in a whiteout is usually not a problem.
Many visitors to
Despite encountering bad weather and warnings at the
Though he reached the crag that now bears his name, only a half-mile from the summit, Ball was repulsed by furious weather and retreated below treeline to spend a first night. He was no luckier in the morning—caught in unrelenting snow and clouds, he wandered all day across the alpine tundra until nightfall, when he again took refuge under the umbrella. Only on the third day did he run into a search party, allowing Ball to avoid succumbing to hypothermia.
The elements are not responsible for all the deaths on
19 people have died on
Hypothermia, falling ice, avalanches, falls, and drowning have killed the rest. The climate of the Presidential Range, of which
Mountains change weather in three ways. They increase wind and precipitation and decrease temperature.
The prevailing wind around
Cotton compares the phenomenon to putting your thumb over a garden hose. As you constrict the flow of water, its speed rises where it can still exit the hose.
At the Observatory, average wind speed is 35 mph, and during the winter, the wind blows above 75 mph every other day on average. At Pinkham Notch, in contrast, about 4000 feet below at the eastern base of the mountain, the average wind is 4 mph.
Pinkham tends to be considerably warmer than the Observatory, too. In the atmosphere, as elevation increases, air pressure eases because there are fewer air molecules pressing down on those below. Molecules therefore expand and cool, which is why temperature usually decreases 3-5 degrees for every 1000 feet of elevation gained. In the winter, the jet stream moves south, bringing a blast of arctic air down with it. The average temperature at the Observatory is 26 degrees—meaning that for most of the year at the summit, precipitation forms as snow rather than rain.
On average, the mountain gets about 21 feet of snow per year. The strong west wind blows most of it off the high ridges and into the ravines on the east side of the mountain, thus making Tuckerman Ravine the premiere location for backcountry skiing in the northeast.
The Observatory staff works two week rotations, with eight days on and six off. Being outdoorsy group, they are often out and about on the mountainside. Neil Lareau, a day Observer, was spotted carving telemark turns down the auto road after the first snowfall in October.
This regional variation happens because air cools as it passes up and over the high ridges and thereby loses its ability to retain moisture. Water vapor visibly condenses and accretes into clouds—it is no coincidence that mountains tend to be wreathed in mist.
Sometimes it is so cold that fog freezes directly onto buildings and plants, creating rime ice. While it has a delicate feathery appearance, rime ice damages trees in the alpine zone by freezing onto windward branches, thus allowing the wind to tear them off the trunk. The trees, if they survive, end up looking like flags or broomsticks, which is how botanists refer to them.
You can usually tell how high snow cover is above treeline by observing how tall plants grow. Anything that sticks out above the snow will succumb to rime ice and wind, so plants adapt by growing out instead of up.
All of these phenomena influence mountains across the globe, but the weather in the Presidentials is particularly potent due to its geography.
Anyone who has spent much time living in northern New England will notice that spells of good and bad weather tend to be brief—usually only a couple of days. This is because the prevailing west winds send alternating high and low pressure systems through the region.
High pressure systems are broad domes of air that can stretch over several states. They generally bring clear skies and cold temperatures. Most air is in the middle, and because air is always trying to equalize pressure, winds blow out from the center and spin clockwise around it.
Low pressure systems, on the other hand, are elongated and form between high pressure systems. They circulate in a counterclockwise direction, and as air blows into the center from high pressure systems, it eventually rises up to make space for molecules behind it. As water vapor gains altitude and cools, it condenses into rain, so low pressure systems tend to be wet.
Indeed, the northeast is a magnet for low pressure systems. Of the 12 major storm tracks crossing the country, 9 of them exit via
“We’re the tailpipe of the
West of Mt. Washington, the next big impediment to wind is the
Thus the area receives a furious infusion of strong winds, cold air, and moisture, making hurricane-force winds possible at any time of year and giving the area a precipitation profile to rival that of the Olympic Peninsula—except that Mt. Washington gets much more snow.
It is not surprising, then, that some American alpinists prepare for the