CHAPTER THREE
THIS LOVE AFFAIR WITH THE SKY
THE URGE RETURNS the way it first began: with a tornado on television. “Tornado!,” a 1985 episode of NOVA on PBS, shadows a team of storm-chasing scientists. They race across the plains, hauling with them a hardened weather instrument dubbed the Totable Tornado Observatory, or TOTO for short. Their goal: to deploy it into the toughest environment imaginable, the heart of a tornado. These men don’t wait for the beast to come to them, they hunt it down—they chase.
This is an altogether novel idea for Tim. Nothing has gripped him like this since he was a kid, when The Wizard of Oz rooted him in his chair at his parents’ dining table.
He wants do what these men do.
Because a smart man does not simply decide one day to take off after a tornado-warned storm, Tim’s forays into chasing emerge gradually. In the late 1980s, Tim is like the swimmer dipping his toe in to test the water. Whenever the big black clouds form over Denver during the late-spring afternoons, he starts to drive out to the edge of town to watch, the way he did when he was in high school. He doesn’t know how to forecast. He can’t tell the difference between a garden-variety rainmaker and a dangerous thunderstorm. He cranes upward at the underside of its gusting advance, watching the clouds flow and break like waves across the surface of the ocean.
Then one day, while his son is still in diapers, this isn’t enough. Tim doesn’t stop at the edge of town. He keeps driving, farther out—and the next time, farther still.
He begins to tackle tornadoes in the methodical way he does everything else: he studies them, figures out how they work, just as he did many years before with his mom’s blender. For the first time in his life he enjoys going to class and sitting at a desk. In 1990 he enrolls in a six-week, forty-hour basic meteorology and storm-spotting course through SKYWARN, a program that trains chasers to become the National Weather Service’s eyes and ears on the ground.
Tim learns all about the parts of the storm he has seen but couldn’t name: that a storm’s monstrous rotating cloud base is called a mesocyclone; that the tornado emerges from the wall cloud, which forms at the bottom of the thunderhead. He learns why Tornado Alley is such a powder keg, with two powerful currents of air—one from the west, dry and warm out of the Rockies; one from the southeast, moist and volatile out of the Gulf of Mexico—colliding here each spring. The atmospheric boundary where they meet is called the dry line, a north-south fissure from Texas to the Dakotas, which acts as a reliable factory for severe storms.
There’s a sequence, Tim learns, to thunderhead formation. At the dry line, the air current out of the west will often sit atop the air from the Gulf, in what’s called a capping inversion or a cap. The top layer then acts like the lid on a heating pot, blocking the lower-level air from rising until it has soaked up enough of the sun’s energy to boil over. The cap can sometimes snuff out a brewing storm, or it can be the starting gun for the biggest behemoths of all. If the volatile Gulf air can break the cap, it races upward, sometimes clocking more than one hundred miles per hour. Thunderheads like mountains in the sky form in moments—all out of a remarkable alchemy of humidity, temperature, pressure, and flow. All out of ingredients that the diligent chaser can monitor and log.
Tim teaches himself rudimentary forecasting the same way he taught himself electrical engineering. Before a chase, he plots a weather map on paper, with an arrangement of dew points and surface observations, usually gleaned from a call to NWS Boulder. After that, it’s a matter of identifying the time and the place where the sky will explode, like a mountain of ammonium nitrate. To be able to predict, drive out, and reap the reward of that first crash of thunder overhead: it’s better than hearing any number of radios crackle back to life.
In the years before smartphones, radar apps, or even the Internet, SKYWARN is the only outlet through which a chaser on the move can access real-time weather updates—short of finding a pay phone. The group has installed a liaison in the Boulder weather service office, who relays the latest information. One must simply set the ham radio frequency to 146.94 kilohertz and tune in.
Before long, Tim is finding himself in the right place at the right time. He’s racing those big black clouds, antennas swaying like reeds from the roof of the Datsun, accompanied by only the sound of Morse code bleating from his ham radio and the baritone wind over the Colorado plains. Weather service radar can detect tornadic circulation within the storm, but that doesn’t always mean a tornado is on the ground. That’s where SKYWARN comes in. The organization’s trained spotters provide what’s known as ground truth. Tim starts volunteering for the role, and he quickly develops a reputation as a spotter whose reports are reliable. He isn’t one of those guys who cries “twister” when he sees stray tatters of cloud or dense rain shafts. No, he’s got an eye for this.
In the early years, his excitement seems directly proportional to the amount of gadgetry in the Datsun. The stuff accumulates like mounds of coral. When there is no room left in 1994, Tim colonizes a used blue ’91 Dodge Caravan he dubs Dryline Chaser. He mounts a crude satellite receiver that allows him to access some low-resolution radar feeds midchase. By adjusting the elevation and azimuth of the dish, he can pick up the Weather Channel from even the most lonesome corners of the state. Next, he defiles the interior of the minivan by sawing a hole into its dash to hold a nine-inch VGA monitor and 486 PC.
