On June 12, 2003, at 0447 central daylight time, two cabin attendants sustained serious injuries when American Airlines Flight 2490, a Boeing MD-82, N491AA, encountered severe turbulence passing through 15,000 feet during descent into Dallas/Fort Worth International Airport (DFW), Texas. American Airlines, Inc., was operating the airplane as a scheduled domestic passenger flight under the provisions of 14 CFR Part 121. The airline transport pilot licensed captain, first officer, 1 cabin attendant, and 129 passengers were not injured. The flight departed Los Angeles, California, at 0052 Pacific daylight time as a nonstop to DFW. Visual meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan had been filed. According to American's flight safety department, the pilot had illuminated the seatbelt sign and had made an announcement for the cabin crew to take their seats because of expected turbulence. The aft cabin attendants went to the rear of the airplane to stow an auxiliary table, and were headed to their seats when the turbulence hit. One cabin attendant sustained a fractured right ankle, and the other sustained a fractured tibia. An aviation routine weather report (METAR) was issued at 0456 local time for Dallas/Fort Worth. It reported thunderstorm and rain activity with an overcast of cumulonimbus clouds at 11,000 feet mean sea level (msl). The remarks section of the observation included frequent lightning occurring inside the clouds, between the clouds and ground, and reaching from one cloud to another.