JetBlue Flight 429, an Airbus A320, was headed from Boston to Sacramento, but had to be diverted to Rapid City, South Dakota, at about 6:30 p.m. (8:30 p.m. ET), spokeswoman Katherine McMillan said. The A320 can seat up to 150 passengers.
Passenger Derek Lindahl said a woman sitting in front of him rose 2 feet into the air in the cabin at one point because she wasn't wearing a seat belt.
"I literally grabbed her out of the air to hold her to the seat," said Lindahl, a software engineer from Sacramento.
Rhonda Renee, another passenger, said the turbulence was like a bad dream.
"People were flying out of their seat belts and hitting their head on the ceiling; it was very scary," Renee said. A flight attendant was assisted off the plane by medical personnel.
Eileen Lynch, a passenger and emergency room nurse who helped injured people aboard the flight, likened the experience to sitting in the "Tower of Terror," a popular, albeit frightening, ride at several Disney amusement parks.
"It just dropped like that without warning," Lynch told CNN affiliate KCRA-TV
It's believed that inclement weather played a role in creating the bumpy flying conditions.
The plane encountered a line of thunderstorms in central South Dakota, according to a flight path analysis by CNN meteorologists Monica Garrett and Chad Myers. After passing through a first storm, the plane came upon a second, which the pilot attempted to fly over or around. The significant turbulence was likely caused by one or both storms.
"While some turbulence can't be detected
on radar, this was not that kind," said Brandon Miller, a producer with CNN's World Weather team. "This turbulence was caused by the rapid rising of air inside the thunderstorms."
"You can see thunderstorms, both from the cockpit and on radar," Miller added. "Pilots know there is turbulence in the storms and do their best to fly around or over them. Although they tried, they could not do that in this situation."
Lindahl praised the flight crew and emergency responders at the Rapid City airport.
"Even though all flight crew were injured in some way, as far as I know, they all maintained their calm and never cracked," he said.
JetBlue sent a replacement aircraft to Rapid City to take the remaining passengers to Sacramento, the airline said in a statement.