On July 19, 2017, about 2245 central daylight time, Republic Airlines flight 4678, an Embraer 170, N427YX, encountered turbulence at about 13,000 ft, during descent to Minneapolis International Airport (KMSP), Minneapolis, Minnesota. Of the 49 passengers and crew onboard, one flight attendant received serious injuries and three passengers received minor injuries. The airplane was not damaged. The regularly scheduled passenger flight was operating under the provisions of 14 Code of Federal Regulations Part 121 from Miami International Airport (KMIA), Miami, Florida, to KMSP. The captain stated that as the flight neared Minneapolis, he turned on the seatbelt sign, just before top of descent, for the arrival into KMSP. He contacted the flight attendants (FA) and briefed them on the weather around Minneapolis and told them to be seated within “about 10 to 13 minutes of the weather”. The first officer then made the descent announcement on the public address system, instructing the passengers to be seated and to fasten their seatbelts due to possible turbulence. Subsequently, during the descent, the airplane entered a cloud and encountered “one swift jolt of turbulence followed by moderate turbulence for a few seconds”. The airplane radar was on but there were no returns in front of the airplane. The captain disconnected the autopilot and maintained positive control of the airplane. Shortly after, the flight crew received a call from a flight attendant reporting injuries to passengers and a FA. The FAs indicated that after the captain informed them of the expected turbulence, they prepared their gallies for landing and made their compliance checks in the cabin. As the aft FA was sitting down in her jumpseat, the turbulence was encountered, and she was thrown into the air and down to the galley floor, injuring her right wrist and left arm. In addition, several passengers were thrown into their passenger service units and one lap-child was thrown several rows away from her mother. The injured FA and passengers were attended to by the uninjured FAs for the remainder of the flight. After landing, the airplane was met at the gate by emergency medical personnel and the injured FA and several passengers were transported to the hospital. The FA was diagnosed with a fractured right wrist and left arm.