Summer Weather Tips

Summer's here, and it means the return of bright, warm weather, an excuse for millions of funseekers to renew their yearly battle with the sun.

  • Some will take home beautiful tans as their prize.
  • Many others will suffer the brief discomfort of sunburn.
  • A few will die, victims of a swift, unexpected killer.


Summer's sudden assassin is heatstroke, an uncontrollable rise in body temperature to over 105°F in a hot environment. A true medical emergency with a mortality rate of 17 to 70 percent, heatstroke kills 4000 Americans yearly, striking whenever people are exposed to prolonged high temperature.

Even in winter, employees of industries using intense heat may be affected. But since hot weather provides more opportunities for people to overheat themselves, most heatstrokes occur during summer.


Heatstroke is caused by failure of the body's heat removal systems. Human life processes constantly produce heat as a byproduct. Normally, this heat production is balanced with heat losses to maintain an internal body temperature of 98.6°F.

In a cool environment, most heat loss is by direct transfer from warm blood flowing through the skin to the cooler atmosphere. As air temperature increases, heat loss by this route slows, and the body cools less rapidly, just as a hot cup of coffee cools less rapidly at room temperature than in a refrigerator. By the time the thermometer reaches 92°F, direct heat losses are so slow, that they cannot remove body heat fast enough to keep up with it's production.

At this point, heat removal by evaporation of sweat becomes essential in maintaining normal body temperature, and the failure to produce or evaporate sweat can lead to a buildup of body heat, a rise in the internal temperature, and a heatstroke.


Collapse of normal temperature control leading to heatstroke tends to affect two very different groups of people.

  • The first, which accounts for only a small part of all heatstroke victims, consists of healthy, young people working or playing hard in hot, humid weather. Included are outdoor laborers, athletes, and military recruits.
  • The second, more highly susceptible group comprises persons with special problems or illness which interfere with normal removal of body heat. Especially vulnerable are infants, the aged, alcoholics, obese individuals, and persons suffering from cystic fibrosis, cardiovascular disease, hyperthyroidism, and fever from infection. Also at risk are those using or abusing amphetamines, LSD, pheothiazines, diuretics, and tricyclic antidepressants.
Diagnosing and Treating Heat Cramps & Heat Exhaustion

The onset of heatstroke is often sudden, especially in the young. But some persons first experience less serious heat cramps or heat exhaustion.

Heat cramps are painful muscle spasms in the legs and abdomen caused by moderate salt depletion from sweating. A more severe loss of salt and water produces heat exhaustion, characterized by headache, dizziness, weakness, nausea, and cool, moist skin.

Persons suffering heat cramps or exhaustion should be moved to a cool are, allowed to lie down, and given Gatorade or a salt solution to drink. They usually do not need to go to a hospital unless heat exhaustion, severe enough to cause unconsciousness, is present. However, they should be cautioned to avoid heat and increase their salt and water intake for the next 24 hours. Neglected heat exhaustion can progress to heatstroke.

Signs of Heatstroke - What To Do

True heatstroke is usually not difficult to identify. The victim either is found in a very hot, humid environment or develops symptoms after air temperature rises above 100°F for several days. He may have complained of nausea, headache or weakness and become confused before losing consciousness. The pulse is rapid and may be either weak or bounding. Respirations are rapid and deep. And most important, the skin is usually flushed, dry, and very hot to the touch. However, these signs are not always present, and heatstroke should be suspected in any person found unconscious after heat exposure.

Once heatstroke is diagnosed, treatment must begin immediately. If permanent damage to the victim's brain, heart, liver and kidneys is to be avoided, his body temperature must be reduced to near normal within one hour. A person suffering heatstroke should be moved to a cool area if one is available. As much clothing as possible should be removed, and the victim cooled rapidly, using ice, cold water, and fanning. Cooling efforts should concentrate on the head, neck, and groin, with a goal of lowering body temperature to below 102°F. While aid is being rendered, an emergency ambulance should be called. Victims of heatstroke must go to a hospital.


While rapid treatment of heatstroke victims is critical, even more important is prevention of heatstroke before it happens. Persons not used to hot weather should limit their activity initially and then increase gradually to allow for adjustment by the body.

Coaches, foremen, and military drill instructors should schedule frequent "cool-off" periods and avoid heavy work schedules on hot humid days. Anyone who is repeatedly exposed to intense heat should wear light, loose clothing and increase his salt and water intake.

Special preventive efforts should be directed toward persons whose age or physical condition increases their risk of overheating.

  • Infants and small children should never be left alone in closed cars.
  • Elderly or disabled persons should not be exposed to the sun's full heat, and should be checked regularly for heat related problems.
  • Persons who have illnesses or take medications which interfere with normal heat removal should consult a physician for advice about their special problems.

The summer heat can be a killer, but with care and common sense there is no reason why everyone cannot enjoy it in complete safety.

Information prepared by the City of Dallas Dept. of Health and Human Services

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