The mother told the emergency services operator she had no idea how long her 2-year-old daughter had been outside in the freezing cold.
She knew only that the toddler was not breathing after finding her on Friday on the family's front porch in Akron, Ohio, where temperatures had been hovering around -9C.
"My daughter, she was outside! My daughter, she's not breathing!" the mother is heard saying in a heart-wrenching 911 recording obtained by the Washington Post. "She is ice cold! She's not responding to me!"
"She's frozen! She's frozen!" the mother screamed frantically.
The toddler, who was identified by the Akron Police Department as 2-year-old Wynter Parker, was rushed to Akron Children's Hospital, where she was pronounced dead, authorities said.
The child's death is under investigation, and authorities yesterday had not said whether charges may be filed in the case.
Police responded about 3.30pm on Friday to the family's home on Doty Dr. The mother - who has not been publicly identified by authorities - told police she had found her young daughter unconscious and cold to the touch on the front porch, authorities said.
The mother later told investigators that she had gone out with her 4-year-old son, leaving Wynter with the child's father, according to a statement from police. The father, who also wasn't publicly identified by police, "works a night shift job and fell asleep," police said in the statement. "The 2-year-old wandered outside the house and was found by the mother when she returned home."
The mother had been away from the house for about two hours, police said.
In the eight-minute audio recording, she told the dispatcher that her daughter "left and went outside."
Asked how long the toddler had been out there, she replied, "I have no idea!"
The dispatcher patiently instructed the hysterical mother to breathe into her child's mouth and start chest compressions while she waited for help, counting with her: "One, two, three, four. One, two, three, four."
"I'm pumping! I'm pumping!" the mother cried, pleading for paramedics. "Where are they? Oh my God, she's not responding!"
After the incident, neighbours grappled with what had happened.
"I cried because I just don't understand how a 2-year-old could be outside and you not know," Crystal Lucas told Fox affiliate WJW.
She added: "It's just a very sad situation. It literally broke my heart."
The Summit County medical examiner's office said it was performing an autopsy Monday afternoon to determine the cause of death.