The summer months are filled with hot days that can put individuals at risk of developing heat-related illnesses, such as heat exhaustion and heatstroke. Heat-related illnesses occur when the body cannot keep itself cool. As the air temperature rises, the human body stays cool when sweat evaporates. However, the evaporation of sweat is slowed down by increased moisture in the air on hot and humid days. When sweating isn't enough to keep the body cool, the body temperature rises and individuals may become ill.