The Oklahoma City Fire Department pulled a male's body out of the Oklahoma River near the dam near Walker Avenue Tuesday morning.
The State Medical Examiner's Office has not released the name of the victim.
Public Works employees discovered the body while checking on the status of a boat that capsized in the storm with nobody on board.
Family members of those swept away by flash floods Friday are waiting to hear if the body found is one of their missing loved ones.
"They won't tell me anything," said Shallen Shrum, who thinks the body discovered is her 21-year-old son Tim Shrum.
Tim and three others, all of them young children, were part of a group that took shelter Friday inside a storm drain near the Dell Call Center under S.W. 15th Street. Everyone was swept into the Oklahoma River.
Shallen's infant daughter and two toddler grandchildren are also among the missing.
Firefighters say they will be searching the river from the Dell Call Center near the Interstate 40/Interstate 44 interchange all the way to Interstate 35.
However, firefighters won't be able to do much more than walk the banks and search for clues. Because the water is rough and filled with storm debris, it may be too dangerous to safely operate a boat.