Storm Chaser Killed in Okla. Tornado
PHOTO: Tim Samaras is seen in his Facebook profile photo. He died Friday, May 31. 2013.

The tornado outbreak that swept through Oklahoma Friday night moved in quickly, for the second time in two weeks, and the cluster of twisters were deadly. In the storm's aftermath, 13 people have been confirmed dead. Among them were three veteran storm chasers.

Tim Samaras, his son Paul Samaras and their colleague, Carl Young, were all killed while trying to document and research the storm.

Tim was found inside his car with his seat belt still on. Paul and Young were pulled from a car by a tornado. One of them was found dead a half mile away.

Tim Samaras, who led the storm chasing team, was an esteemed scientist. In the storm chasing community, he was known, not only as one of the best, but one of the most cautious. He chased because he wanted to learn, find out how to improve warning systems and help meteorologists do a better job of forecasting tornadoes.

Much of Samaras' recent research was funded through National Geographic, which issued a statement today that said, "We are shocked and deeply saddened... [Samaras] was a courageous and brilliant scientist who fearlessly pursued tornadoes and lightning ... in an effort to better understand these phenomena."

I first learned of Tim Samaras from his research. He was a scientist who had the record pressure drop inside a tornado from one of his probes. Years later, I met him while shooting "Storm Chasers" on the Discovery Channel. He was a mentor and hero to my then boyfriend, Reed Timmer.

"He always knew what he was doing and he's always been controlled and safe and it just doesn't make sense," Timmer said of Samaras' death.

Carl Young was part of the research group Samaras founded called TWISTEX, or Tactical Weather Instrumented Sampling in Tornadoes EXperiment.

Last August, we documented one of Tim Samaras' scientific expeditions for "Nightline." Samaras and his son took us along on Samaras' quest to document the birth of a lightning strike. On our trip, he showed me his baby, the Kahuna, a camera that can slow motion-capture at 1.4 million frames per second -- it is possibly the fastest camera in the world.

I stood in his kitchen as father and son gave one of their many goodbyes to Samaras' wife, Kathy. They hugged and she told them to be safe.

With the Kahuna in tow, Samaras took us on an 800-mile journey across Colorado, New Mexico, Kansas and Oklahoma, hoping to capture the exact moment that triggers a lightning strike.

"Why does [lightning] choose a target like a tree instead of a building or building instead of a tree?" he said at the time. "You know, perhaps some of the imagery that we collect in the field may help answer some of those questions."

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But Samaras also was well aware of the real dangers of storm chasing.

"At times I have mixed feelings about chasing the storms," he said. "On one hand they are incredibly beautiful, on the other hand these powerful storms can create devastating damage that change people lives forever."

At the end of our chase last year, Samaras told me it was his desire to know more, to inform us all, that fueled him to keep going out into the storm again and again.

"I don't know how many storms I've seen in my lifetime, but every single one of them, I still get pretty excited," he said. "The little boy in me just wants to come out here and just watch and stare."

READ: Lightning Safety 101: How to Protect Yourself

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