How long can a person survive in a locked car?

Survival in a locked car varies based on several factors, including temperature, humidity, and the individual's health. In extreme heat, a person can suffer from heatstroke within 30 minutes to an hour, as temperatures inside a car can rise significantly above outside temperatures. In cooler conditions, survival could extend to several hours or even longer, but dehydration and other risks still pose serious threats. Ultimately, quick rescue is crucial for survival in any scenario.