USA.GOV — Extreme heat can be very dangerous, leading to heat stroke and death. Heat stroke occurs when your temperature rises quickly and your body cannot cool down. This condition is life-threatening, but it is preventable.

Tips for Preventing Heat-Related Illness

• Stay in air-conditioned space if possible. If your home      is not air-conditioned, go to a public library, heat-relief shelter, or      other cool location.
• Drink plenty of non-alcoholic fluids (check with your      doctor if you are usually supposed to limit your fluids).
• Wear loose-fitting, lightweight clothing.
• Cut back on exercise.
• Closely watch those who are at high risk of      heat-related illness, including older adults, young children, and      individuals with physical and/or mental illnesses.
• NEVER leave anyone in an enclosed, parked vehicle.

If you believe that you or someone else may be suffering from heat stroke or another heat-related illness, get help right away. It could be a life or death emergency.