Oklahoma Tornado Video: Deadly Chickasha Twister Caught On Camera Moments After Forming

When Steve Sisemore went to the Chickasha, Oklahoma, Walmart on Tuesday night to shop for dinner, he did not expect to encounter a tornado in the store's parking lot.

Sisemore witnessed the development of the Chickasha tornado that would later kill at least one person as it tore through this small town southwest of Oklahoma City.

"We saw it develop right out of the sky," Sisemore told The Huffington Post. "You could see the cone starting to drop. You could see two debris fields starting to develop."

Sisemore said that he was about 200 yards away from the tornado when he began filming it with his phone.

"This is very humbling," he said. "When it develops and you see the magnitude of it and feel the intensity of it all you can do is just stand and watch and respect it, because there's nothing you can do."

Deadly storms swept through Oklahoma, Kansas and Arkansas Tuesday night killing 13 people.

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