Remember to never leave kids or pets in the vehicle during the summer while it is off. As soon as it turns off, the temperature can reach dangerous levels quickly. On a day that is about 85 degrees, it can reach over 100 degrees in a short amount of time. This can happen in as little as ten minutes. So even if you want to run into a store quick, if you become distracted it will be over ten minutes. Even if you decide to crack the windows, it will get extremely hot in the vehicle for those in it.
As the vehicle heats up, it will start to act like a greenhouse. As the sun goes through the windows it will start to warm the vehicle up. It will also cause the dashboard and seats to heat up as well. This will produce even more heat for the interior of the vehicle. If the windows are not down, then there will not be any air circulation inside the vehicle. Parking in the shade will only make it a couple degrees cooler, but not enough to make a noticeable difference.
If you typically do not take your kids to daycare and then have to one day, make sure to remember to drop them off. One way to remember to look in the backseat is to place anything you need for work back there. This will ensure you open the back doors and check the seats. Some newer cars have technology installed that will alert you for anything that might be in the back seat of your vehicle. This is a great reminder to look in the back for any children, pets, or even groceries. It is also a good habit to get into if you check the back of the vehicle.