A 6-month-old boy died after being left for hours in a hot car in Louisiana, authorities said.

       The baby was found dead in the backseat by his parent at about 5:46 p.m. Tuesday, according to the East Baton Rouge Sheriff’s Office.

       When the parent went to pick up the baby from day care after work, they realized they forgot to drop him off at day care that morning, the sheriff's office said.

       The heat index -- what temperature it feels like with humidity -- reached a scorching 112 degrees in Baton Rouge on Tuesday.

       The investigation is ongoing. The coroner will conduct an autopsy to determine how long the baby was in the car, according to the sheriff's office.

       At least 16 children have died in hot cars across the U.S. so far this year, according to national nonprofit KidsAndCars.org.

       Since 1990, at least 1,100 children have died in hot cars -- and about 88% of those kids were 3 years old or younger, according to KidsAndCars.org.

       Click here for hot car safety tips to keep in mind this summer.