The science behind storm chasing

For the last several years, Tim Samaras has led TWISTEX — Tactical Weather Instrument Sampling in/near Tornadoes Experiments — one of three pursuit teams on Discovery Channel's "Storm Chasers."

The documentary/reality show was not renewed for 2012, but the public fascination with tornadoes prompted the network to recently release "Storm Chasers: Greatest Storms," a DVD of the program's most hair-raising segments.

On "Storm Chasers," Samaras, an engineer, built and tweaked the meteorological equipment, which was rushed to tornado sightings and placed where the twister was headed. Finding the one-shot, right-spot place to leave the probe involved monitoring an array of other instruments - radios, scanners, tracking devices and more.

Not your typical science-geek line of work.

Samaras, 52, talked about that - and tornadoes - in a recent interview.

Q. What led you to extreme meteorology?

My interest in the science of weather stems from when I was a little kid growing up in Denver. I remember being affected by watching "The Wizard of Oz" - and that lit my passion for tornadoes. I was also one of those kids who is always taking things apart to see how they worked.

My academic background is in electronics engineering - measuring natural phenomena that are near-impossible to gauge, like energetic materials (those with high amounts of chemical energy that can be released).

I made measurements of blasts. For example, I helped to test a system that would protect troops: a polymer coating that can be sprayed inside the doors of Humvees. Instead of having troops test it, we put a dummy in the Humvee and measured the blast pressure.

I come up with the ideas and technology to do this kind of thing.

My passion for storm chasing allowed me to develop instruments and tools to make measurements inside of tornadoes - 250 mph winds. Nobody was able to do this until 2003, when I was able to measure the pressure drop inside of a tornado. It was 100 millibar: basically, one-tenth of the atmosphere.

Q. That was the bridge into television?

Tornadoes seem to attract attention. When I recorded the millibar measurement, it got on the news and became national news.

One thing led to another. When Discovery Channel conceived the "Storm Chasers" show, it originally featured Sean Casey, who drives the tornado intercept vehicle, and Dr. Josh Wurman, who runs the Doppler on Wheels. They ran the show a couple years on Discovery. When they asked me to come aboard, I was flattered. I was with them for three years running.

Q. Do you have a family? What do they think of your going around chasing tornadoes?

I'm married; we have three kids who are adults now.

My wife has known about this passion of mine for 25 years. And for all that time, I've never had a bad incident chasing tornadoes.

Believe it or not, it's not the tornado that is the hazard - it's the driving. Every year, our group drives approximately 40,000 miles in 11 weeks, and that's a hazard if you stop and do the math. During that time, you may have a couple 'down' days - but other times you drive 1,000 miles in a day, including in the middle of the night on two-lane roads. That's what I worry about.

Here's why: We drive into the path of a tornado, drop the instruments, then quickly get out of the way. We always have to have a way out.

Q. What 11 weeks are you talking about?

Approximately the middle of April through the middle of June, plus or minus a few days here and there. The weather dictates when we start and stop.

Q. Do you warn people against chasing tornadoes?

Don't do this at home. Absolutely. I give lectures around the world about storm chasing and get a lot of questions.

I don't discourage their love of this. All I ask is that they contact their local National Weather Service and get spotter training - to learn how the atmosphere works, where you should safely be. And even after that training, I advise them to chase with someone who know the details and can show them the ropes.

Q. For the rest of us: What's the single most important thing to know?

What to do when your area is under a tornado warning or watch.

Many people tend to ignore morning weather forecasts, especially in spring, but you need to be somewhat weather savvy: Most - but not all - tornadoes occur between 3 and 7 p.m., when the temperature is at or near the day's high: It takes cold and warm air to collide in a certain way to create a tornado.

So it's smart to tune into local weather. What's happening today? Any chance of tornadoes? Will our area be under severe weather watch? Are conditions good for tornadoes?

A "watch" means conditions are good for tornadoes. You need to be extra vigilant.

A "warning" means a tornado has been spotted and is in progress, and you need to take immediate action.

The most important thing is to have your family practice ahead of time so that everyone knows what to do. Had everybody, say, in Joplin, Mo., known what to do - whether they were in a vehicle, house or mobile home - I think the death rate would have been much lower. That was a late-afternoon tornado on May 22 last year that caused 160 deaths.

Right now is when you need to get up your plan: What to do when you hear there's a warning, and you have to act on it in 10 minutes.

Q. Like where to go?

Exactly. And what to take.

In a vehicle, if there's no way to escape the area, get out and seek shelter in a culvert. In a mobile home, seek shelter elsewhere. Have your cellphones with you. Agree on a place to meet after the tornado passes, in case you're separated.

In a home, go to the basement, get under a pool table or workbench and cover your head. If you're in a house with no basement, go to an interior room - a closet or bathroom.

The bathroom is the best place to go if you don't have a basement or storm shelter: You're away from windows and the plumbing strengthens the walls. Drag a mattress from your bed, then get in the bathtub and cover yourself with the mattress.