Hot Car Deaths Nearly Triple So Far This Year

— -- It is every parent's worst nightmare.

A bad day at work. Trouble at home. Or just general stress. There are so many triggers for forgetfulness, but there are few worse consequences than leaving a child in a hot car.

The latest example is the child who died in Baton Rouge, Louisiana, Wednesday after prolonged exposure to heat in a car, marking the 11th such U.S. death this year.

There had only been four of those deaths this time in 2015, according to the National Safety Council, which is a 275% increase.

The child in Louisiana - an 8-month-old girl - was left in a car for about two hours Wednesday when the temperatures could have reached as high as 130 degrees, police told The Associated Press.

She was the second child to die of vehicular heatstroke in 24 hours after a police officer left his infant son in his vehicle in Rome, N.Y., Tuesday.

The official start of summer isn't until June 20, but it still only takes a few minutes for a car’s inside temperature to reach life-threatening levels, according to the National Safety Council.

The deaths may be more common in southern states, but hot car deaths occur throughout the country, according to the nonprofit.

Wednesday was National Child Vehicular Heatstroke Prevention and Awareness Day, and grieving parents sent a letter to Anthony Foxx, secretary of the Department of Transportation (DOT), and Dr. Mark Rosekind, administrator for the National Highway Traffic Safety Administration (NHTSA), calling for immediate action, according to KidsAndCars.org.