Heat

Hot Weather Hazards

Sunburn:

  • Symptoms: Red and painful skin. Severe cases result in swelling of the skin, blisters, fever, and headaches.
  • Treatment: Lotion or ointment. If blisters break, cover them with dry sterile dressing. Extreme cases should receive medical treatment.
  • Prevention: Apply sunscreen frequently, especially when swimming or sweating. Protect all exposed skin whenever outdoors by wearing a hat, long sleeved shirt, and long pants. Stay inside during the late morning and early afternoon.

Heat Cramps:

  • Symptoms: Heavy sweating and painful muscle spasms, usually in the legs but sometimes in the abdomen.
  • Treatment: Apply firm pressure to or gently massage the cramping muscles; sip water, but stop if nausea occurs.
  • Prevention: Avoid strenuous physical activity during hot weather, drink water frequently.

Heat Exhaustion:

  • Symptoms: Heavy sweating; cool, pale, or clammy skin; fast and weak pulse; body temperature normal to elevated (103 degrees); headache, dizziness, or fainting; muscle cramps; nausea.
  • Treatment: Get victim out of the sun, preferably to an air conditioned room. Have him/her lay down, loosen their clothes, and apply cool wet cloths. Give sips of water, but stop if nausea occurs. If vomiting continues, get medical assistance.

Heat Stroke:

  • Symptoms: High body temperature (106 degrees or higher), hot dry skin, rapid and strong pulse, fatigue, dizziness or fainting, nausea or vomiting, possible unconsciousness.
  • Treatment: Get medical assistance immediately, then move victim to a cooler location, preferably to an air conditioned room. Remove his/her clothing and reduce their body temperature with a cold bath or sponging with a cloth. Do not give fluids to the victim.

Heat Index: Hot Temperatures and High Humidity

The Heat Index, or apparent temperature, is a measure of the combined effect of heat and humidity on peoples' ability to maintain a normal body temperature. To dissipate excess heat, human bodies pump more blood into the blood vessels near the skin. Water passes through the skin surface as perspiration. The body heat evaporates the perspiration to cool the body. High humidity slows the evaporation rate, so the body works harder to cool itself or finally becomes unable to maintain a normal internal temperature.

Heat disorders are likely during prolonged exposure or strenuous physical activity when the Heat Index is over 105 degrees; temperatures in the 90s with 60% relative humidity can raise the Heat Index into this danger category.

Heat Index values were developed for shady conditions with light winds. Full sun can increase the Heat Index by as much as 15 degrees. Strong winds, especially during hot dry conditions, can also cause severe problems such as dehydration.

A Heat Index Chart is available to determine the Heat Index.

View Heat Index forecasts.

Hot Weather Safety

Heat-related illnesses can result from exposure to hot humid conditions in just a few hours. Many people develop medical problems during the first few hot days when they are unaccustomed to the heat and have not reduced activities. However, affects of heat on the body are cumulative, so prolonged heat waves can stress people enough to cause death.

Children, elderly people, and people with health problems or taking certain medications are more susceptible to heat disorders because their ability to sweat is insufficient to dissipate heat. People not acclimated to very hot weather or who overexert themselves can also become victims of heat.

Residents of large cities have a greater risk of developing heat-related conditions because urban areas are hotter than rural areas. Buildings and streets are made of concrete, asphalt, bricks, and other materials that absorb heat during the day and slowly release it at night, making temperatures warmer both during the day and night. Heat waves are often accompanied by stagnant air masses, which increase the concentration of air pollutants that add to health problems.

Although the northern Plains region does not often have high humidity levels, hot temperatures and strong winds can also cause heat-related disorders. When temperatures rise; reduce your outdoor activities, stay in cool shady locations, and follow these guidelines to allow your body to adjust to the heat.

General:

  • Eat more frequent, small meals. Reduce the amount of high protein foods, which produces metabolic heat.
  • Drink plenty of water to avoid dehydration even if you don't feel thirsty. Drink smaller amounts of water frequently rather than a large amount once in a while. Avoid alcoholic, carbonated, or caffeinated beverages.
  • Wear one layer of loose-fitting, lightweight, light colored clothing. If your clothing becomes wet or damp, change them.

Outdoors:

  • Perform strenuous activities during the morning or evening when temperatures are cooler and the sun is less intense. If you must be outdoors during the afternoon; try to remain in the shade, move slowly, and take frequent breaks.
  • Wear a wide-brimmed hat.
  • Use sunscreen. Sunburn can greatly reduce the body's ability to dissipate heat.
  • Do not leave children or pets inside a vehicle with the windows up. Temperatures inside a closed vehicle can reach 140 degrees in just a few minutes.

Indoors:

  • Use air conditioning or fans. If air conditioning is not available, stay on the lowest level of the building or go to a public facility or home of a friend or relative during the hottest time of day.
  • Take a bath or shower with cool water.
  • Keep window shades, curtains, and blinds closed. Keep lights off or low. If nighttime temperatures cool off, open windows at night, then close them in the morning.

Download the Heat Wave brochure; published by the American Red Cross, Federal Emergency Management Agency, and National Weather Service.

View Ultra Violet Radiation information.

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