It happened just before 1:30 Tuesday afternoon in Tulare County.
When deputies arrived, they say the car was turned off and all the doors & windows were closed.
First responders treated the four-month-old on scene, where she was then rushed to the hospital.
The young baby has since been released.
The Tulare County Sheriff's Office is investigating how and why the infant was left there.
"I'm not sure exactly how it became noticed that the baby was not inside the home," said Ashley Ritchie with the Tulare County Sheriff's Office. "I do know that the grandfather was the one that called 911."
When deputies found the baby, she was responsive and conscious.
But also very lethargic. Ritchie said they're optimistic that the young girl will be okay.
"That really is a miracle for a four-month-old baby to be stuck in a hot car on one of the hottest days of the year for more than two hours," said Ritchie. "For her to survive that is, in my opinion, a miracle."
Deputies took the 30-year-old mother into custody where she was booked into Tulare County Jail for child endangerment.
"Obviously child protective services will conduct its own investigation to see what the next steps need to be," said Ritchie.
Almost two weeks ago, Clovis police arrested another mother for child endangerment, after she left her 18-month-old child in a hot car.
It happened at a McDonald's on Willow and Nees.
"She had an older child with her," said Sgt. Abby Padgett with the Clovis Police Department. "They went inside for approximately 20 minutes to eat and they left an infant child in the hot car."
Police said that's when a concerned citizen noticed the car was turned off and the windows were slightly down.
Paramedics checked out the child, and said the baby was warm but healthy.
Both children were given to their father by Child Protective Services.
"With these temperatures cars can heat up very quickly," said Sgt. Padgett. "They can heat up to deadly levels."
Numbers from Kids and Cars Safety show, nationwide this year, nine children died after being left in a hot car. One of the deaths happened in San Diego County.
"Children can actually heat up three to five times faster than an adult," said Dr. Hailey Nelson, a pediatrician at Valley Children's Hospital. "That's really why it's so dangerous for them."
With more triple digit temperatures ahead, Dr. Nelson, is stressing this reminder for families:
"In addition to always being careful when we're transporting our children and taking them out of the car locking your vehicle is really important," said Nelson. "So a child can't go play in there."
Clovis Police say, if you see a child or pet stuck inside a hot car, call 911 right away.
The agency also adds to make sure you stay with the vehicle and look for any signs of heat-related distress.
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