As a reader of his magazine, I came to the conclusion that an interest in disembodied weather history – in weather history for its own sake – is the surest sign of the genuine weather-weenie. Paul Kocin did not need to admit his past to me. I had already seen his book, Snowstorms along the Northeastern Coast of the United States: 1955 to 1985, and I understood his predicament: We live in a society that does not reward these efforts. Try discussing forgotten weather with strangers and watch their reactions. Pilots, too, will grow impatient. They navigate through history without the education to make sense of it. That is why I felt lucky to find Kocin: He was just the man to rescue my storm from its passing.
We spread the relevant weather maps on a conference table. Kocin started with a regret that my students and I had missed the more interesting conditions. It so happened that the day before our departure from San Francisco, a tightly wound low had left the Canadian plains and sailed fast to Alabama. Kocin called it an ‘Alberta Clipper’ and said he remembered this particular one for its turbulent wake. And that was nothing compared to events of the following morning when, as we lifted off from the West Coast, a complex system of twin storms and connecting fronts formed on the other side of the nation. Research meteorologists are still sifting the data to explain what happened next.
That gray winter morning Kocin had just assumed his duties in the operations room when he noticed that the atmospheric pressure at a weather station in Georgia had dived sharply and climbed again. Kocin watched with growing excitement as the next station to the north reported the same phenomenon. The pressure drop was as catastrophic as a crash, and it seemed to be moving quickly up the Eastern seaboard.
Kocin faxed the first hastily scribbled alert to the regional forecasting centers: ‘Possible gravity wave!’
He got the warning out just in time. The wave sped into Pennsylvania and New England like the impulse of a whip. Cities reported incredible snowfall rates of up to six inches an hour. Weather enthusiasts rushed to their stations. Citizens were amazed to see lightning and to hear the snow thunder. Traffic snarled. Across the Northeast a million little invasions were delayed.
Our Pacific storm lacked that punch. Kocin worked diligently to help me understand its birth, but his attention kept drifting back to the pressure drop in the East. He truly regretted that we had missed it.
I did not have to remind Kocin that on that first day New England remained out of reach of our slow airplane. I wanted to keep the conversation focused on our storm, now in the Midwest. Kocin said he understood, but a little gulf had opened between us: Weather watchers are drawn to history’s most violent weather, but pilots are drawn to the weather they have flown.
I tried to describe the conditions we had encountered on the flight from Kansas City to South Bend. Kocin listened politely but remained unimpressed. He had the advantage of trusting the weather map. This was hardly surprising. Theoreticians and practitioners will often disagree. And ordinary history usually looks more orderly from a distance than from up close. Kocin doubted, for instance, that we had found much bad weather in South Bend. He mentioned perhaps some trivial lake effect.
But the weather in South Bend seemed plenty bad to me. The storm was advancing fast and was now expected to slip eastward along the air-mass boundary and into Massachusetts by the next morning. We decided to cross the notorious Alleghenies and spend the night in Harrisburg, Pennsylvania. It would be a hard-fought flight most of the way there, but for the next day it would gain us maneuvering room over the coastal plain, with its low cruising altitudes and its frequent well-equipped airports. If everything went according to plan, the storm’s center would pass over us while we slept. In the morning we would head for Boston and hit the weather again from the south.
In the meantime, the weather conditions had worsened in South Bend. Bundled against the cold winds sweeping the airport, we fueled and checked the airplane. By the time we taxied out, in late afternoon, the visibility had dropped to a third of a mile in heavy snow. In principle such visibility was less than we would need to see the runway at the end of an instrument approach should we encounter a problem after takeoff and need to return, though in a true emergency we felt we could in practice make it to the runway. Conditions ahead for 200 miles looked almost as low. The tops were expected to be at 22,000 feet, about our capabilities. The airlines were reporting moderate turbulence. The only good news was that the temperatures remained too cold, probably, for icing to threaten us.
We took off and were swallowed by cloud. The effect was immediate and dramatic – the ground vanished so quickly that it might never have existed. Indiana became an abstraction, South Bend an uncertain memory. The clouds were rough, but it was the psychological severity of this transition from the ground to the weather that made the airplane difficult to control. I asked the pilot beside me at the controls to stop throwing switches, to stop writing down frequencies and fuel settings, to stop listening to the Morse identifiers of the navigational stations, and please simply to concentrate on flying. A good pilot is one who knows when not to follow procedures.
The thin voice of air traffic control, with a woman’s laughter in the background, offered a thread to the Midwest, but for us the world had been reduced again to the instrument panel. We were tired and did not talk. We were together, but also each of us was alone. The flight passed not by the minute or hour but, as flight often does, in a suspended condition of time, an abstraction of speed disconnected from progress across the surface of the earth. Harrisburg existed merely as the anticipation of a faraway descent through the clouds. There was nothing to do about it yet. We flew on in a meditative mood. The airplane ran strongly. The landscape that surrounded us was one of our own making.
Night came at 9,000 feet in continuing cloud and snow. Our forward lights bored horizontal holes into the blackness through which snowflakes rushed back at us in frenzied assaults. Out at the wing tips, the strobes caused the night to bloom. We did not exclaim over the beauty of this wilderness but recognized it as fully involved participants, judging our surroundings critically because the conditions remained rough and hostile.
Over eastern Ohio we broke suddenly into the clear air of an Arctic night. The lights of Cleveland lit the northern horizon. The air-mass boundary lay just to our south, in the black wall of cloud from which we had emerged. Paul Kocin would have been delighted with the view: The weather lay exactly where the map said it should. We sailed over Pittsburgh, which was still digging out from Kocin’s gravity wave, and we hit the clouds again for the brief crossing of the Alleghenies and the high-speed descent into Harrisburg, where we landed on an icy runway. We were content then to let the storm center pass overhead.
In the morning we woke to a heavy snowfall outside the hotel windows and realized immediately that the weather had gone wrong. Rather than tracking as forecasted to New England, the storm had slowed over the Mississippi and had assumed a classic stance, extending a cold front southwest across Oklahoma and a stationary front eastward across the Virginias to the Chesapeake. Along the stationary front now, warm sluggish southern air was trying to climb the dense Arctic air that had parked at low altitude over the Northeast. Harrisburg lay in the thick of the resulting disturbance. The woman on the Weather Channel sounded tense and excited.
We got a ride to the airport and telephoned for a formal weather briefing. The ceiling and visibility were close to the minimum requirements of the instrument approach. And the temperature gradient looked ominous: On the ground it registered a normal twenty-one degrees, but rather than cooling further with altitude, it stayed about the same, just below freezing, to a point near the tops of the clouds. A DC-9 climbing out of Harrisburg reported heavy icing from the surface all the way to 16,000 feet – conditions too deep and dangerous for our unprotected wings. There would be no escape after a takeoff. The storm had grounded us. We settled by the hangar telephone and waited for a break.
Ice on any airplane is scary stuff. Allowed to accumulate, it distu
rbs the lifting air flow across the wings and tail and causes them finally to stop flying. When the wings stop flying, the airplane does one of two things: It descends into a flat, mushing, semi-controllable impact with the ground; or it shudders, drops its nose, maybe rolls, and hits the ground much harder. When the tail stops flying, the effect is even more dramatic: The airplane dives violently, irreversibly, and may gain so much speed that it breaks apart even before it hits the ground.
Other complications are possible. The American Eagle ATR turboprop that crashed at Roselawn, Indiana, in October 1994, was a new design with an unexpected vulnerability to ice, which under narrow circumstances caused the airplane to roll out of control. Immediately after the accident, pilots at the airline’s Chicago base balked at continuing to fly that type of airplane into winter weather. The company answered with apparent concern, suggesting that the pilots seek psychological counseling. Pilots everywhere smiled bitterly. The fear of ice is a healthy and rational emotion.
Still, ice can become an obsession. Once you start looking for it you see it all around. Watch an airplane standing on the ground in sleet or freezing rain. Ice accumulates in glistening sheets across its top surfaces. Airport crews spray it off with an alcohol mixture before the airplane taxis. If there is a delay before takeoff and the ice comes back, the crews have to spray it off again. Some airliners have crashed because of the inconvenience of that second deicing, which may require a return to the ramp. The resulting delays are measured by the hour. In response, a few airports have installed taxi-through spray racks near the runways. Pilots need no counseling to use them.
Once an airplane takes off, the obsession changes. Now you see ice growing forward from the sharp leading edges – on the wings, tail, and engine nacelles. If the airplane is propeller-driven, you imagine it on the spinning blades, where it grows even faster. In-flight icing may come from sleet or freezing rain, but more commonly it comes from the super-cooled water particles that make up the clouds at temperatures between thirty-two and about fifteen degrees Fahrenheit. Super-cooled water particles are droplets floating in such perfect equilibrium that they maintain a liquid form in below-freezing air. Then along comes the below-freezing airplane. The disturbed droplets turn instantly to ice and stick to its leading edges. The effect is that of a telephone pole in an ‘ice fog.’ Only here the wind is blowing several hundred miles an hour. Because of the airplane’s speed, the growth can be explosive and can lead to loss of control within just a few minutes. The critical load varies, but beyond perhaps three inches of ice, flight becomes a gamble. Airliners are protected by heated leading edges, or by rubber boots which inflate to knock off the load once it accumulates. Our airplane had no such devices. So we waited in Harrisburg.
By noon we had ruled out New England, where the conditions had started to duplicate our own, but the weather to our south was opening. Cloud bases at 2,500 feet were reported over Wilmington and Washington, D.C., and the surface temperature at Norfolk was an ice-melting forty-five degrees. The cloud structure looked loose enough to allow us escape routes once we got up into it. Harrisburg was still clamped down, but we prepared the airplane for a fast getaway and a flight to Norfolk.
The break came in mid-afternoon with a slight raising of the ceiling. Having warned the air traffic controllers that we would need an immediate return to Harrisburg should we discover no way through the ice, we took off and climbed aggressively into the weather. And we found a way through. Slipping and twisting to stay clear of the heaviest clouds, we passed Philadelphia and Wilmington. Near Baltimore, we began to see a bit of the ground – glimpsed through holes in the clouds, a patch of brown farmland, a forest of leafless trees, a stretch of sad gray water and marshland. Fifty miles later, over the middle of Chesapeake Bay, we ran entirely out of weather and changed our destination to Richmond, where we landed, refueled, and rethought the storm.
We went back into it after dark on a round trip to Wilkes-Barre, Pennsylvania, where the weather looked worst. The flight was not dangerous, but it was rough and involved. Again, ice was the problem. The stationary front had turned warm and was moving up the Eastern seaboard. In the blackness of the clouds we took ice and shed it, and kept repeating the cycle. At Wilkes-Barre we flew the instrument approach through cloud and falling snow, saw the runway lights, and pulled up without landing in order to avoid delays on the ground. Deep in the weather, we turned south for Richmond.
It was late at night. The storm had developed with unexpected strength. We stayed low, fighting forty-mile-per-hour head winds at 3,000 feet. To the left, the only other pilots on the frequency, a Delta crew, got blown off the instrument approach into Allentown and had to circle back to try again. Despite the south winds, the air temperature at our altitude was a frigid fifteen degrees. The clouds were thick with moisture. Outside of Philadelphia, with a splatter that sounded like sleet, we began to ice heavily. I shined a light on the wing and saw the ice growing like a voracious parasite. It looked white and crusty on the leading edge and clear where it streamed back over the wing. Within a minute we had taken more than an inch – a rate of accumulation that required immediate action. We gambled on a quick climb to 7,000, where we found warm Georgian air that melted the ice and slid it in sheets from the wings.
Had the gamble of that climb not paid off, and fast, we would have fallen back on our second plan – a quick retreat downwind into the frigid air to the north and a high-speed approach to a long runway. The high speed would have been necessary because iced-over wings stall at above-normal speeds. It would have complicated the landing, but we knew the airplane and thought if we could make the pavement, we could come to a safe stop.
All that proved to be academic, however. Having found the layer of warm air, we crept comfortably through the clouds to Richmond, welcoming the moisture rolling up our windshield, listening to the first reports of freezing rain on the surface in New Jersey. In the morning we saw the headlines about an unexpected ice storm in New York. People as usual were blaming forecasters for the mess.
Pity the forecasters. Of all the sciences, theirs is the most public. Here is a short version of its evolution. Emergence from the sea came first, followed by speech, followed by talk about the weather. Then came sacrificial rites, followed by the idea that peasants might pay a tithe to priests to keep the sky in order. Aristotle had the brains to separate the atmosphere from the heavens. He wrote Meteorologica, the first unified weather theory, around 340 BC. Two thousand years later, René Descartes doubted his methods and applied new rigor to the ignoring of God. In 1637, as an appendix to Discours de la méthode, he published ‘Les Météores,’ an explanation of the weather. Modern meterology is essentially his child. Descartes suffered from a lack of weather data, since in the seventeenth century the basic instruments for measuring the air were still being invented. Credit Galileo with the thermometer, his student Torricelli with the barometer, and French intellectuals in general with the discovery that atmospheric pressure rises and falls with weather and altitude. Acknowledge various Europeans for their wind and humidity instruments, for their discoveries in physics, then jump to the mid-1800s, to places like Ohio, where the telegraph suddenly allowed news about the weather to travel faster than the weather itself.
National governments now set up weather services to collect observations and issue forecasts. At last a modern relationship could develop between the weather wizards and the public they served. It was a terrible shock. In England, the esteemed meteorologist and admiral Robert Fitzroy, who had captained Darwin’s Beagle on the famous voyage of scientific discovery, was in 1855 named director of the first British weather office. Fitzroy was a good man, but like other nineteenth-century meteorologists he suffered from some misleading ideas about the nature of storm systems. Over the next ten years, he issued a series of dramatically bad forecasts. When the public finally noticed, a popular new sport was born. Fitzroy’s last forecast was apparently the worst. Ridiculed by loftier scientists, attacked in the press, he d
id the right thing and shot himself. Maybe his old friend Darwin could have explained why forecasters today seem less sensitive.
Some seem almost belligerent. At the Camp Springs Operations Center, I asked the forecaster in the office next to Paul Kocin’s about the kind of forecasts that gave him satisfaction. He fixed me with a hostile stare.
Satisfaction?
In the winter, he wanted to know about his damned drive home from the office. In the summer, he wanted to know about his damned backyard barbecue. That was enough for him. He did not expect the National Weather Service to organize his life for him. In the days leading up to his daughter’s outdoor wedding the weather was unsettled, and so rather than complaining about the forecast he put up a damned tent.
He was a wounded man. As I left he said, ‘If people would just verify all our forecasts, all the times we call for no rain and get it right, they’d find our accuracy skills somewhere above 90 percent.’
Naturally. Most weather is good, most of the time. This means that most forecasting is inherently easy. For instance, I predict that Las Vegas will be hot and sunny on July 4, 2026. And at small risk, I can go farther. My forecast for Nashville on the same day is: partly sunny, high near ninety-two degrees, chance of afternoon thundershowers. Also, I think I’ll issue a flood watch.
I mentioned my confidence to Keith Seitter, the assistant director of the venerable American Meteorological Society, based in Boston. His attitude was more philosophical than that of the angry forecaster in Camp Springs. He said, ‘Sure, but we know those aren’t the calls that buy us dinner. We get paid for the good storms, the ones where we say, “Okay, the time has come to batten down the hatches.”’
Poor Fitzroy. He stumbled away from dinner in 1861, about fifty years early. At the start of the twentieth century a Norwegian mathematician named Vilhelm Bjerknes made an assertion that only then became obvious: The future form of the weather is determined entirely by its original form, acted on by the known mechanical and thermal laws of physics. This meant that numerical weather prediction was theoretically possible – you could start with a numerical map of a storm, and then apply a few equations.
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