BACKGROUND: The National Weather Service is expanding the number of Heat-Health Watch Warning Systems to every city with a population greater than 50,000 people. The systems measure air masses that affect health, particularly in urban centers, which often suffer from too much heat. Excessive heat is the top weather-related cause of deaths. In the U.S., about 1500 deaths from excess heat occur every summer.
WHAT IS HEAT STROKE: The body controls heat through the hypothalamus, an area of the brain that secretes chemicals to control the body's metabolism. The amount of heat the body produces is balanced naturally with the amount of heat lost through sweating. Normally, sweat evaporates from the skin. But if someone is exposed to high heat and humidity, the air is already saturated with moisture and the sweat will not dry quickly enough to cool the body. The body loses water content, along with essential body salts. If the body's core temperature gets high enough, the brain will overheat, causing the person to become disoriented or aggressive; he or she may even begin to hallucinate.
WHAT TO DO: Heat stroke can quickly lead to disability or death, so it's critical to begin cooling efforts immediately until medical help arrives. For example, remove the victim's clothing and apply cool water to skin, then fan the victim to induce sweating. You can also apply ice packs to the groin and armpits; immerse the victim in a tub of cold water or cold shower; or spray the victim with cool water from a garden hose.
REDUCE YOUR RISK:
- Drink plenty of fluids when outdoors on a hot day: two to four glasses every hour. Avoid tea, coffee, soda or alcohol.
- Wear lightweight, tightly woven but loose-fitting clothing in light colors.
- Wear a hat, sunglasses, or use an umbrella to protect yourself from the sun.
- Try to schedule vigorous activity and sports for cooler times of day.
The American Meteorological Society and the American Geophysical Union contributed to the information contained in the TV version of this report.