On December 26, 2015, at about 1238 pacific standard time, Southwest Airlines flight 5895, a Boeing 737-700, N7733B, encountered moderate turbulence while descending for approach to San Diego International Airport (KSAN), San Diego, California. Of the 148 passengers and crewmembers onboard, one flight attendant received serious injuries and the airplane was not damaged. The flight was operating under 14 CFR Part 121 as a regularly scheduled passenger flight from Denver International Airport (KDEN), Denver, Colorado, to KSAN. The flight crew stated that turbulence encounter occurred as the airplane was descending through about 14,000 feet and the seatbelt sign was illuminated. At the time of the turbulence encounter, the three flight attendants (FA) were standing in the aft galley preparing to secure the cabin. When the turbulence began, all three FAs attempted to brace themselves but one FA was unable to grab an assist handle by the galley when she thrown to the floor. She was unable to stand back up on her own and required assistance from the other FAs. After landing, the injured FA was transported to a local hospital where she was diagnosed with a fractured ankle.