Extreme heat can be rather uncomfortable. But what actually happens to the human body as the mercury rises? On humid days, when the air is already saturated with water, sweat evaporates more slowly. This explains why it feels so much hotter in high humidity. When relative humidity reaches a high enough level, the body's natural cooling system simply can't work. Sweat evaporates very slowly, if at all, and the body heats up. According to the Mayo Clinic, the most serious level of this breakdown is heat stroke, and it occurs when the body’s temperature reaches an excess of 104 degrees Fahrenheit. During heat stroke, body functions grind to a halt, the brain shuts down the body’s natural coolant system, perspiration. Without sweat, the body can no longer keep its temperature in check, heat stroke causes the brain to swell, leading to headaches and even seizures in more extreme cases. Victims also experience an altered level of consciousness. The cardiovascular system is affected as well. Heat stroke causes blood pressure to drop and the heart to beat faster and more irregularly, heightening the risk for high-output cardiac failure. Heat-related deaths are one of the deadliest weather-related health outcomes in the world, in the United States an average of 658 people a year die due to extreme heat. AccuWeather’s patented Realfeel temperature is a measure that combines the effect of temperature, humidity and other factors. On May 19, 2007 in Pakistan, severe heat and humidity created deadly RealFeel temperatures. In Sibi, northwest Pakistan, the temperature reached 115 degrees with a dew point of 90; the RealFeel was 150 degrees, one of the highest ever recorded.
Learn more about your ad choices. Visit podcastchoices.com/adchoices