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Data jockeys tackle the chaos of severe weather

At the national Storm Prediction Center, meteorologists work non-stop to forecast the tornadoes and severe thunderstorms that plague the U.S. CNET Road Trip stopped by to visit.

Last summer, CNET reporter Daniel Terdiman got caught in this severe thunderstorm. Only, he didn't know it would be so bad until he was driving directly through it. After visiting the national Storm Prediction Center, he knows how he could avoid the same mistake. Daniel Terdiman/CNET

NORMAN, Okla.--Driving east through Iowa last summer, a bank of darkening clouds hovered to the north. Thinking I could outrace them, I kept going. Soon, I was engulfed by a severe thunderstorm with near zero visibility, heavy winds, and torrential rain. It was the worst storm I've ever been in.

Obviously, I made it out alive, but I'd taken a very foolish risk. As a Californian, I was unfamiliar with the danger posed by even the slowest-moving storms. Even more foolishly, I failed to bring along with me any of the many tools that would have alerted me to the impending danger.

That was one of the first things I learned from a visit to the National Weather Center's Storm Prediction Center here, a place where teams of the world's top meteorologists work 24/7/365 to spot severe weather and, more importantly, get out the word. Of course, that's useless if the public isn't listening. As Keli Pirtle, my host for the visit put it, "If people don't receive the information and act on it, then why are we here?"

More on that in a moment.

A look at the weather 'mosaic' for the southern United States for Friday, July 18, showing plenty of strong weather, including thunderstorm activity throughout the region, courtesy of the National Weather Center. National Weather Center

As part of CNET Road Trip 2014, I've come to Norman, a city of 116,000 people in the center of Oklahoma, and home to the main campus of the University of Oklahoma, for an up-close look at how the federal government evaluates ever-changing weather in the continental United States in order to forecast the kinds of storms -- tornadoes and severe thunderstorms, for the most part -- that cause the most danger to people's lives and property. Oklahoma, of course, is in the heart of Tornado Alley, the area of the Great Plains that is the most-frequently hit by those most destructive of weather events.

The Storm Prediction Center is part of the National Weather Service, and is funded by NOAA, the National Oceanic and Atmospheric Administration. But while it does the severe weather forecasting for the lower 48 states, it doesn't issue the warnings you receive on the radio, TV, or through a variety of available mobile apps.

Those are put out by a collection of 122 local offices around the country that get their information from the SPC via "outlooks," issued as much as seven days in advance. They predict the likelihood of anything from tornadoes to severe thunderstorms to wind or hail.

A week out, those predictions can be vague. But as Pirtle explained it, the meteorologists are refining them every day, with the targeted areas getting smaller and smaller and the specific location more and more specific as an event gets closer.

'It can be sobering'

For people like John Hart, the lead forecaster at the Storm Prediction Center, watching serious storms develop is a mixed bag. On the one hand, he and his fellow meteorologists have spent their whole careers learning how to differentiate the storms that pose real peril from those that are harmless.

When something serious develops, it can be exciting, he said, and it's also when he and his team put out their "big products," the outlooks that go to the local weather offices. But there's obviously a flip side, too. "There's no doubt it can be sobering," Hart said, "to be watching a very significant event unfolding. Maybe we'll be seeing a tornado going through a town or city, and we have information on where it's hitting, and the people there may not know it. There are times when we are watching history, and watching this horrible stuff unfold."

Lead meteorologist John Hart peruses the many monitors and the 'firehose' of weather data he looks at daily to try to spot severe weather well before it develops. National Weather Center

Added Hart, "Hopefully, we've done our best" to warn people.

On a normal day, Hart, like his fellow meteorologists in the SPC -- the "data jockeys" -- sits at a desk, a bank of computer monitors in front of him, each portraying a different set of data or weather model. There's real-time satellite data, radar data, and information on surface temperatures, winds, moisture, and even lightning strikes. With a click of his mouse, he can zoom in on any area in the lower 48, looking for trouble. Hart summed it all up nonchalantly: "It's just a matter of taking all this data and integrating it into what's happening now and in the future."

On the one hand, the work is about managing all that data, staying in front of the "firehose," he said. But without question, there's an art to Hart's job. Part of that is understanding the subtleties of weather, and the endless data flowing in, and knowing how to shift the views on his monitors so that he can try slightly different angles from the satellite views, for example, to see something he might have otherwise missed.

'Rockies eastwards'

Though severe weather can hit just about anywhere, the vast majority of it in the United States takes place in the "Rockies eastwards," Hart said.

These events can occur at any time of day or night, and throughout the calendar. But the bulk of it hits during spring and early summer, he explained, especially when it comes to tornadoes.


More adventures from Road Trip 2014

Check out the latest from Daniel's trip to the best tech spots in Texas, Oklahoma, Kansas, and more.

    Although the science of predicting tornadoes is extremely imprecise, Hart said there are a few major reasons that April through early June is tornado season. To begin with, warm water in the Gulf of Mexico sends air currents northward, where it can meet winds and high temperatures coming off the Rockies. The right combination of those two factors can be the starting point for the kind of supercells, or rotating thunderstorms, that spawn tornadoes.

    Though most supercells won't produce tornadoes, sometimes winds near the surface are set up just right to generate first what's called a mesocyclone -- a strong rotation, very low to the ground, in the thunderstorm -- and then, if the spin tightens enough, a true tornado.

    At any given moment, that cycle can break down, meaning there won't be a twister. "Tornadoes are a very delicate and complex balance," Hart said, "because of things we don't understand very well."

    And that's the sticky truth about the severe weather prediction business. Even the world's best meteorologists can't successfully predict every tornado with enough warning time to save everyone. "We don't understand why, even on the same day in the same storm," Hart said, "this [area had a] tornado, and this other one didn't."

    Which means that some of the most essential data the SPC has at its disposal is the historical record: When and where did previous tornadoes happen, or not happen? Though it's just one data point, it can help with the prediction.

    Then again, there's also basic probabilities, Hart said: The more storms there are in an area, the higher the odds something severe will occur. There's usually dozens of storms converging on an area during the biggest tornado outbreaks, he said. Though we may only hear about one tornado -- when it flattens a town, for example -- there may be dozens more that touch down during the same time frame, and in the same geographic area. In 2011, a particularly bad year for tornadoes, a storm formed that affected between six and eight states from the Mississippi River to North Carolina, Hart recalled.

    But at the core of this is one basic truth that everyone at risk from tornadoes, and everyone trying to protect them, has to deal with: It's pure chaos out there. "Even with the best of the science [at our disposal], we can't tell what storm at what moment" is guaranteed to produce a tornado, Hart said. "There's not a lot of hope for that. It's a lack of [scientific] understanding, not a lack of data."

    Then he added,, "There's still a lot of big Eureka science left" to be done in the field.

    In the event

    Not long after my visit to the SPC, I spoke with Hart again, by phone. As we spoke, he and his team were dealing with a series of severe thunderstorms that were slamming the eastern seaboard, from New York City to Philadelphia, and on down to Baltimore and Washington, D.C. At the same time, Florida and Texas were both dealing with severe weather, as were the Rocky Mountains in Colorado.

    Hart didn't sound too worked up about these storms, but then again, he seemed like the kind of person who keeps an even keel even during the worst weather events.

    That's important because it's his job, and that of his fellow meteorologists, to stay calm and help everyone involved, from the national to the local level, decide what to do when weather hits.

    A Storm Prediction Center 'data jockey' constantly scans several computer monitors looking for evidence of severe weather. National Weather Center

    In the event that something serious begins to brew, the data jockeys at the SPC will start to analyze the data coming in, blending their years of expertise with the raw data, to identify small areas where the risk of severe weather is growing.

    If it looks bad, Hart said, the SPC will send out a "discussion," alerting local offices that there's concern about an area. At this point, it is just concern, and all that may be necessary is a "watch," letting the public know that they should be alert.

    But if things get more serious, it's time for Hart and everyone else involved to have a conference call where he'll explain his thought process, and listen to the feedback from the folks on the ground in the local area that may be affected.

    If he issues what he calls a "coordinated watch," it'll now be up to the local office to issue the actual severe weather warnings that will be disseminated through the many channels that feed the public: local media, weather apps, and so forth.

    'Most looking for the door'

    There are countless meteorologists, but just a few that have what it takes to work in the SPC, 22 at the moment, to be precise. To begin with, the work starts with a lifelong passion for understanding severe weather, Hart said. Though a bachelor's degree is the minimum education required for a job at the SPC, there is no specific additional experience required. Rather, it takes getting hired at the National Weather Center and then convincing the higher-ups that you've got the talent -- and the makeup -- for the job.

    A sign that can be placed on the door of the Storm Prediction Center. It was not posted when CNET Road Trip visited. Daniel Terdiman/CNET

    That's key, since the job can be extremely stressful, Hart said. "Most meteorologists shy away from severe weather," he said. "Most are looking for the door when it happens. These people have to love it."

    Added Hart, "There are definitely some people better suited to this than others. I would liken it to medicine: Doctors who enjoy the emergency room, and those who don't like the stress of it."

    'A couple hours'

    Though the SPC sometimes issues outlooks as much as seven days ahead, tornadoes can often form with just a couple hours' notice. It all depends on the storm.

    Fortunately, Hart said, the biggest storms -- the ones posing the highest degree of danger, that are the SPC's "bread and butter" -- are ones that everyone sees coming well ahead of time. "Environments that create big tornadoes," Hart said, "stick out like a sore thumb."

    In those cases, everyone is usually on board, from the SPC to the local offices, and thanks to copious amounts of information issued through all the various channels, down to and including tornado sirens that go off in the towns in danger, few are surprised when the twister touches down.

    That's not to minimize the impact such events can have on these towns and cities in terms of death and destruction, but it's clear than in most cases these days, many people's lives are saved thanks to the information that first emanates from Hart and his colleagues.

    Perhaps the real danger is in the heart of Tornado Alley, when warnings followed by no actual tornado are so frequent that people begin to tune out.

    Pirtle, my host for my visit to the SPC, called this the "False Alarm Rate" and said that one reason there may have been so many casualties in Joplin, Mo., when it was slammed by an EF5 tornado -- the strongest on the Fujita scale -- on May 22, 2011, causing 158 deaths, was that the city hears warnings "all the time."

    Everyone involved in the severe weather prediction and alerts business is trying to figure out how to reduce the False Alarm Rate, she added, and that's one reason the coordination between the SPC and the many local offices is so crucial. And, it's ultimately why the actual warnings come from the local offices.

    Still, the system can work exactly as intended. In Greensburg, Kan., for example, the May 4, 2007 EF5 twister that destroyed 95 percent of structures in the town of 1,400, was preceded by its tornado siren sounding non-stop for 20 minutes. Even in a place accustomed to warnings, that kind of alert gets people's attention. Though 12 were killed, it could have been far worse. Indeed, the town's leaders, realizing the fearsome power of the impending storm and expecting complete tragedy, ordered refrigerated trucks capable of holding hundreds of bodies be routed to Greensburg.

    Weather apps

    Thinking back to my experience in Iowa last summer, I now know how naive I was to be driving into an area frequently slammed by severe weather without any system that could protect me. I was listening to satellite radio, which usually doesn't broadcast weather warnings, and I didn't have any kind of weather app that would push warnings to my phone.

    In other states, I had been receiving automatic severe warnings that are issued through the mobile service carrier, so perhaps I figured I was covered. But Pirtle said that system is inconsistent at best. A much better way to go, if you're going to be in an area that is prone to severe weather, is to listen to local radio, and upload one of the many weather apps that are specifically tailored to delivering real-time weather warnings.

    The Iowa severe thunderstorm that CNET reporter Daniel Terdiman got caught in last summer, as seen once Terdiman escaped it, luckily all in one piece. Daniel Terdiman/CNET

    In fact, Pirtle said, for the system to work best, it's recommended that people rely on multiple methods for getting their weather warnings, in case any one of them fails. And, she said, have a plan in place.

    For me, I'm now taking this advice much more seriously. As I set out on a recent leg of my journey, knowing I was driving through open country in the Great Plains, I loaded up an app called Weather Radio, and was very happy to receive several alerts as I drove into areas that were under flash flood warnings.

    But I didn't get any warnings when, suddenly the skies opened up and the Mercedes-Benz E250 Bluetec I'm driving on Road Trip 2014 was pelted with gumball-sized hail. It seems the system still has room for improvement.

    Keep an eye out for more behind-the-scenes stories and photo galleries as I travel throughout Texas, Oklahoma, Arkansas, Tennessee, and Kansas during this year's Road Trip. I'll seek out most interesting technology, military, aviation, architecture, and other destinations our country has to offer. From U.S. Air Force basic training to NASA's Johnson Space Center and FedEx's massive package-sorting hub, and much more, Road Trip 2014 will take you along with me.