The NTSB released their factual report reporting, that the flight’s dispatch package contained significant meteorological information (SIGMET) Victor 1, which indicated occasional severe turbulence between 14,000 feet and FL240 also reporting turbulence had been reported by flightcrews. Based on that SIGMET the dispatcher planned the flight for 13,000 feet.
Air Traffic Control in Saint Louis discussed the potential of turbulence with the flight crew and suggested 15,000 feet would be a better option to avoid turbulence than 13,000 feet. The captain therefore change cruise altitude to 15,000 feet. The crew decided to keep the fasten seat belt sign illuminated for the entire flight.
When the flight attendant began cabin service the aircraft encountered light turbulence, about halfway through the service the aircraft went through moderate turbulence. The flight attendant locked the cart and took a seat. After the turbulence diminished about a minute later the flight attendant resumed service.
via Accident: Chautauqua E135 near Milwaukee on Nov 30th 2010, turbulence injures 10.