Correspondent Peter Van Sant reports on the effects this storm had on two families caught in its grasp.
Gary England, a veteran meteorologist for KWTV, the CBS News affiliate in Oklahoma City, had never seen anything like it. "This was bigger, meaner, uglier, nastier than anything I had ever imagined," he says.
It was the start of a catastrophe. During the next 11 hours, 65 tornadoes tore through the Oklahoma landscape, in the worst outbreak in the state's history.
England and his team of storm chasers broadcast warnings over TV and radio, trying to save lives.
"This is extremely dangerous," England told viewers at one point. "So you folks in the path of this tornado, get below ground. If you can't do that, get in the center part of your house."
Tom Tinneman, who lived in Bridge Creek, Okla., saw England on television. He heard something in the forecaster's voice that gave him pause.
"He was telling you to get underground," Tinneman remembers. "I wish I could have (gone) underground." Tinneman and his family lived in a mobile home, without a storm shelter nearby.
As he listened to England, Tinneman looked at a map and realized that the tornado was right on top of him.
Samantha Darnell and her husband, Deon, who lived only a few miles from the Tinnemans, were with his parents. They didn't know the storm was coming. "My dad and I both looked out the window, and there was just this huge, black wall coming straight at us," says Deon Darnell.
"I was so scared; I was petrified," Samantha Darnell remembers.
While thousands of people were trying to get out of the way, University of Oklahoma Professor Josh Wurman was heading toward th storm. Wurman is a tornado chaser. On May 3, he came within a mile of the most powerful tornado ever recorded.
"A violent tornado is one of the strongest forces of nature on the planet," Wurman says. "The damage really can be compared to bombs. Bricks and wood and pieces of plants that are moving at 300 miles an hour become lethal missiles."
The Midwest is known as Tornado Alley. In the spring, winds from the Gulf of Mexico travel in one direction, while air from the jet stream travels in the other. Sometimes, moist, turbulent air between the two winds starts rotating. Under certain conditions, thunderstorms can turn and stretch that rotation into the vertical plane, extending downward into a tornado.
Reaching its peak strength near Bridge Creek, the May 3 tornado touched ground in the Oklahoma City area for almost an hour and a half, much longer than an average tornado. It gouged its way across southwestern Oklahoma.
"I think the potential was there for hundreds, even thousands of people to be killed," says Wurman of the storm.
Tinneman and his two daughters, Tawny and Kylee, were caught in their mobile home when the tornado approached.
"I saw just a big black wedge, and not realizing that was the tornado, I thought, 'Well, it's in there somewhere,'" Tinneman remembers.
He took cover in the closet with his two children. "Then the last sensation I remember was kind of how you go over that first big hill of a roller coaster," he says. "The house first just kind of started to tremble, and I felt the tie downs break loose on one side of the trailer, and we started to roll over. It was like it picked the whole home up, threw it down and threw us free of all the debris." He thinks the trailer was thrown about 100 yards.
Deon and Samantha Darnell, the couple's 3-month old infant, and Deon's parents, all crowded into the closet of a two-story house.
"It just sounded lke a huge - a beast!" Deon Darnell remembers. "I heard the windows just being shattered out of the house."
The tornado pulled the house off its foundation. "You could literally hear the boards splinter in the house, and the house was just being torn apart," says Samantha Darnell.
Deon Darnell's mother was the most badly hurt. "It just looked like somebody had tried to tear her arm off," he says.
After the tornado, Tom Tinneman didn't know what had hit him. "I thought we'd been in a car wreck....And then it dawned on me that it was the tornado. And then it dawned on me, 'Where's my children?'"
To find out what happened next, go to Afterward A Paramedic Works Alone.