At around 11:23 a.m. police say a woman called to report another woman unconscious in her children's backyard pool in the 100 block of North Tennessee Avenue.
Rescuers arrived to find 52-year-old Greta Gray dead.
Gray is a neighbor of the woman who called for help.
Police say preliminary information indicates Gray had a pre-existing medication condition that may have contributed to her death.
An autopsy is scheduled for Wednesday.