Police and the Cumberland Fire Department say the woman, 54, was found at her home on Maryland Avenue at 5:15 a.m. They say when they arrived she was found unconscious fully submerged in the bathtub.
The victim was transported Western Maryland Regional Medical Center, where she was later pronounced dead.
Investigators with the Allegany County Combined Criminal Investigation Unit and Maryland State Police Forensic Sciences Division say there was no sign of trauma to the body or obvious cause of death.
Investigators say the body is being sent to the Maryland State Medical Examiner's Office in Baltimore for an autopsy to determine the cause of death.