The National Safe Kids Campaign says about 30 children are killed each year because they were left in hot cars.
Since kids bodies warm three to five faster than an adult, their bodies cannot compensate for the intense heat like a healthy adult.
Brian Taylor, a paramedic with REMSA, says they see the aftermath of leaving kids in a car.
"The car is going to increase the intensity of the sun. It acts as a terrarium. It's going to increase the temperature quite a bit. Last time we checked, one day, when it was 90-degrees outside, it was well over 140-degrees in the vehicle."
We did our own test as well, sitting in the shaded seat of the car for just a short period.
It got very hot, very fast.
After just ten minutes with the windows cracked the temperature quickly rose to 120-degrees.
After another ten minutes, the temperature rose to 140-degrees in the direct sunlight.
Heatstroke occurs when the body temperature hits 104-degrees, that's why experts say cracking the window does little to change the temperature inside a car.
"Even if you have the vehicle running and the air conditioning turned on. The vehicle could turn off. The vehicle could not be able to keep up the air conditioning with the heat."
Laura Bylsma says even her 8 and 9 year old could be old enough to leave alone, but she still doesn't even think about it and now that she has a six month old baby, it's a hard habit to break.
She says those who come close to forgetting the kids should probably slow down anyway.
“You don't leave them at all. It's too hot, it's too dangerous. They can get into trouble even if they're safe. So, I haul them everywhere."
With temperatures already hitting triple digits across the state, paramedics say if you even see a child left in a car, it's important to call 9-1-1 immediately.