It started as a small heap of fluffy white clouds on a blue summer day. But as the afternoon wore on, the sky above the flat green plains of Oklahoma darkened and grew malevolent. Crackling, roaring and rotating, the thunderstorm touched down as a tornado at 6.03pm, 13 kilometres south-west of the town of El Reno, unleashing a sudden and terrible power. In less than a minute, the tornado blew up from about 1.6 kilometres wide to 4.2 kilometres, the widest ever measured, with wind speeds close to 480 kilometres per hour, matching the fastest on record. Revolving around the immense parent tornado were smaller satellite tornadoes. One picked up a car containing three storm researchers, who'd been laying down probes to measure the system, and tossed it into the air, killing all three.
"You just saw the very left edge of the tornado but you couldn't see the right edge, it was so wide," says storm chaser Daniel Schummy, a 22-year-old graphic artist and video editor from Jimboomba, Queensland. On May 31 this year, Schummy was directly in the tornado's path, stuck in a traffic jam with three other storm chasers from Australia: Justin Noonan, Brendan Strauch and Rosemarie Steiner. The local TV news station's chief meteorologist had been telling people to get in their cars and flee south.
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"I said to the guys,'We have to get as far south as we can, because if something happens and we get caught in traffic, we are gone. It is as simple as that,' " says Noonan. While people in cars panicked, the giant tornado crossed the highway behind them and turned north-east. "If the tornado had turned right, there would have been thousands of people dead," says Noonan. "I woke up that morning and sent a message on Facebook telling my girlfriend how much I love her, because I was fearing for what might happen that day. All the parameters were at the high-end range of intensity."
Agrees Strauch, "It wasn't an elegant, picturesque-type situation ... it was such a behemoth of a storm and an ugly, messy system. It just looked so angry."
The El Reno tornado considerately raged mainly over open terrain and farmland. It killed 18 people and injured 115, but if it had hit Oklahoma City, 40 kilometres away, there would have been devastation of biblical proportions. Three kilometres to the north and it would have taken out the entire town of El Reno. Instead, it waltzed 26 kilometres along the Interstate 40 highway where, at 6.40pm, it subsided as quickly as it had started.
For those drawn to extreme weather, seeing a mighty, historic storm is the holy grail. But the elation is tempered by the knowledge of the powers of destruction that these storms carry. Storm chasers congregate in "Tornado Alley" - northern Texas, Kansas and Oklahoma, where warm, moist air from the Gulf of Mexico pushes across the plains to meet cold, dry air from the Rocky Mountains, creating the supercell thunderstorms that produce tornadoes. "It's just so geographically unique over there," says Strauch. "It's not like anywhere else on planet Earth."
The wheat plains of Kansas, the pastoral flatlands of the American mid-west, dotted with wooden farmhouses and barns, provide a picturesque backdrop to these great menacing gargoyles charging across the landscape, destroying much or all in their path. "You get beautiful countryside and beautiful storms," says Schummy.
"Early to end of May is prime time," says Noonan, 28, an electrician whose family have a farm south of Brisbane. "There are so many other ingredients, but the two currents colliding are the real catalyst for what can come." Noonan has been coming to the US since 2010, and has developed a reputation as a "tornado whisperer" - a talent for reading the elements and spotting exactly when and where a big storm will form.
This had been Schummy's first trip to the US. Back in the serene beauty of the Gold Coast hinterland, he's a world away from nature's fury. "Sometimes it feels surreal," he says. "When you are within a few hundred metres, you can hear the roar of the wind swelling the tornado. That is really something."
You have to wonder about the psychology of the thousands of people who chase storms. Says Noonan, "It stems from fascination. Most people I know who do this were either scared or fascinated as a child. A big flood in 1996 really kicked it off for me. I was scared and fascinated, but that flood really got things firing along. After that, I was making my own weather charts. When I finally got my driver's licence in 2001, I went for my first chase and have been doing it ever since."
Schummy was petrified by storms and lightning as a young boy and as he grew older, tried to overcome his fear. "I started doing lots of research into thunderstorms in my last two years of school, 2007-08. By the time storms struck south-east Queensland in November 2008, I was tracking severe storms on radar after school."
As a child, Rosemarie Steiner, 37, who works in hospitality, loved The Wizard of Oz, in which a tornado sweeps away a Kansas farmhouse. "I've loved storms for many years. I lived in the Grampians for a while," she says, referring to the Victorian mountain range, "and we saw a lot of extreme weather out on the farmland. Unpredictable weather and cloud formations fascinated me; it just grew from there."
Strauch, 31, from Melbourne, who works in the automotive industry, was also transfixed by The Wizard of Oz. "I remember being mesmerised by the shape and movement and emotion of what a tornado can do ... and finding a blue sunny sky boring. People ask, 'Why would you a) put yourself in that situation, and b) want to be involved in that sort of devastation?' But that's really got nothing to do with it. From a scientific point of view it is just a thing of beauty, watching the atmosphere create something like that. "
The adrenalin hit is also addictive, says Steiner. "When we'd get to the hotel at night [after a twister], we'd be up for hours, just buzzing and going through our photos. Some of us were living on three or four hours' sleep a night, because we were still pumped from what we'd seen the day before."
Staying in cheap hotels and eating fast food, the storm chasers will drive through the night to get up close and personal to a tornado in the making. "Once the chase is on, the chase is on," says Schummy. "You don't even stop for a toilet break, you are just focused on the storm."
Noonan compares a tornadoes to a runaway train. "It is deafening, a massive roar. You can see the debris shooting around it and ... you just sit back and go, 'Wow, this is Mother Nature at her best.' Every storm has got its own tale to tell."
This year has been an alarmingly bumper year for tornadoes. Less than two weeks before El Reno, only 40 kilometres away, one ploughed into the city of Moore, leaving catastrophic damage in its wake. Twenty-four people were killed, 277 injured and at least 1500 homes destroyed. Entire subdivisions were flattened, and debris was scattered so far that interstate highways had to be shut. Witnesses described it as "a giant black wall of destruction". Like the El Reno twister, it was given the highest rating on the Enhanced Fujita tornado damage scale, an EF5 - but it was less intense. "A telltale sign of an EF5 is bark being stripped off trees," says Noonan. "So you can imagine what it would do to a human being."
The Australian storm chasers made a difficult call on the Moore tornado. "We decided to head south and pick up radar instead of risking our lives," says Schummy. "When we picked up reception, we could actually see the storm going right through the centre of town and knew people were going to get killed, and the town destroyed."
Adds Noonan: "It is a sinking, sinking feeling." A sensible decision meant they were 80 kilometres away, but they drove through the aftermath days later. "Just driving along the highway, it went from a few trees being snapped, to a few houses being de-roofed, to complete destruction."
As news of the Moore tornado's devastation emerged, they still had no reception. Back in Robina on the Gold Coast, Noonan's fiancée Hayley Summers spent some anxious hours. "I couldn't get hold of Justin and I had no idea where he was or if he'd been caught up in it," she says. "Usually we have pretty good contact. But it is the unknown. It is those moments when you don't have contact and you know something bad is going on that you do freak out a little bit. But he loves it, he is so passionate about it ... and I love him, so I'm on board."
Daniel Schummy's girlfriend, Ashley Dawson, a university student who works in a shop at night, didn't want him to go. When he was out of contact, she was especially worried. "I basically sat on Facebook because that was our form of communication; I went through the weather sites trying to get someone to tell me what was going on. It was pretty terrifying finding out at work what had happened. I closed the shop and went home. I was freaking out. It is a nerve-racking pastime; it would be nice if he had a normal hobby."
A perfect storm, then, is a well-behaved one that is pretty, obligingly puts on an electric light show, sends out a few pyrotechnics, but goes about its business away from people and where they live. "If it's the middle of a paddock, it's the most beautiful thing to see, quite extraordinary," says Schummy.
Using GPS and a wireless connection with a big booster aerial to locate the target area, the thrill is watching a force of nature build until all the necessary elements are aligned: wind shear, instability, moisture, helicity values (a measurement of vertical wind shear), cold upper temperatures, and a strong up-draught. "When nature creates a big tornado, everything has to work just right," says veteran storm chaser Roger Hill, who gets tourists up close to twisters via his company, Silver Lining Tours. "I think being able to make a weather forecast and pick the right place at the right time is part of the satisfaction and part of the adrenalin rush."
But to get close enough to see all the pieces of the unpredictable puzzle come together also requires exit strategies - and never moving more than five metres from the car. "No matter how safe and cautious you are, nature can always throw a curve at you, so you always have to be very watchful and ready for anything to happen," notes Hill.
Noonan insists that he has never feared for his life. But even he was shaken by his close shave in Joplin, Missouri, in May 2011, when the deadliest tornado since 1947 killed 158 people and injured 1500 others. Noonan and his crew had come into town for fuel, but were turned away because the area was under a tornado warning. "At the time, we didn't understand why this was, so we mulled around a little bit and cleaned the windscreens. We got back, looked at the computer and there was this incredible storm ... this monster coming at us at 35 miles [55 kilometres] an hour."
Driving through town, they were stopped at traffic lights on the way. "We could see it destroying the outskirts of the town. We were coming down the main street, and it was coming directly across us, 300 metres away. It was monstrous and very dark." They started running red lights and nearly took shelter at a local branch of hardware megastore Home Depot. "Thankfully we didn't," says Noonan. "Home Depot got 'relocated'. "
When power was cut and the traffic lights went dead, they were able to speed out of town, which undoubtedly saved their lives. "As we blasted onto the interstate, trucks were being rolled over in front of us - big semitrailers. It was just so close."
Noonan recorded the experience on his video camera. "You can hear that my voice is about to break up. I am like, 'We have got to go back and help these people.' And then hearing the reports that came in afterwards, it broke my heart. I had quite a bit of post-traumatic stress. I really struggled to come to grips with it all."
Nonetheless, he still lives and breathes big-weather events. In the calm of his home, he revisits some of his best storm-riding moments by editing footage he's taken - and saving money for his next big trip. "Mother Nature just blows you away with the power and beauty of it all," he says. "She likes to show you how insignificant you are at times. I tell people that once they've seen this, they'll never look at a cloud in the same way again."
Schummy, too, has learnt deference, "for nature and storms. They mean business. As beautiful as they are, they are deadly."
And they will both be in Tornado Alley again next May. Without question.
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