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Extreme Heat

Heat is the number one weather-related killer in the United States. Heat kills by pushing the human body beyond its limits. In extreme heat and high humidity, evaporation is slowed and the body must work harder to maintain a normal temperature.

photo of a Caution Extreme Heat sign

Conditions that can induce heat-related illnesses include poor air quality and little to no air circulation. As a result, people who live in urban areas may be at greater risk from the effects of a prolonged heat wave than those living in rural areas. Also, asphalt and concrete store heat longer and gradually release heat at night, which can produce higher nighttime temperatures.

Conditions that May Result from Extreme Heat
Condition Symptoms First Aid Response
Severe Sunburn
  • Skin redness
  • Pain
  • Possible swelling
  • Blisters
  • Fever
  • Headaches
  • Take a shower
  • Use soap to clean skin
  • Apply dry, sterile dressing
  • Seek medical attention
Heat Cramps
  • Painful spasms (in legs or abdomen)
  • Heavy sweating
  • Move to cooler location
  • Gently stretch muscles to relieve spasms
  • Sips of cool water every 15 minutes
  • No caffeine, no alcohol
  • Discontinue liquids if nauseated
Heat Exhaustion
  • Heavy sweating
  • May be cool, pale, flushed or have normal body temperature
  • Fainting, dizziness
  • Exhaustion
  • Headaches
  • Lie down
  • Loosen or remove clothing
  • Apply cool, wet clothes or towels
  • Fan or seek air conditioning
  • Give sips of water if awake
  • Sips of cool water every 15 minutes
  • Discontinue liquids if nauseated
  • Seek immediate medical attention if vomiting begins
Heat Stroke
  • High temperature of 103°F+
  • Hot, red, dry skin
  • Rapid pulse, weak or strong
  • No sweating
  • Dizziness, nausea and confusion
  • Possibly unconscious
  • Danger! Call 9-1-1
  • Move to cooler location
  • Remove clothing
  • Cool bath, sponging or cover in a cool, wet sheet
  • Watch breathing
  • Use extreme caution
  • Use fans and air conditioners

NOAA can issue the following heat-related products as conditions warrant. During extreme heat emergencies, you can find detailed information on your local TV and radio, the National Weather Service, and NOAA.

Take Action Before a Heat Emergency

Preparing for extreme heat can protect your family. There are steps you can take to make your home a better place to stay during periods of extreme heat.

Steps to Be Ready

  1. Complete the Family Emergency Plan pdf file and discuss it as a family. This is a simple way of keeping each member of the family informed on critical information: where to reconnect should you become separated, who to call, and what you will do should an excessive heat emergency occur.
  2. Complete the Emergency Contacts Card pdf file and place one in your Emergency Kit.
  3. Prepare an Emergency Kit. The Emergency Kit should be easily accessible should you and your family be forced to shelter in place (stay at home) for a period of time.

Take Action in your Home

  • Install window air conditioners snugly; insulate if needed.
  • Check air conditioning ducts for proper insulation.
  • Install temporary window reflectors for use between windows and drapes, such as aluminum foil-covered cardboard, to reflect heat back outside.
  • Weather-strip doors and sills to keep cool air in.
  • Cover windows that receive morning or afternoon sun with drapes, shades, awnings, or louvers. Outdoor awnings or louvers can reduce the heat that enters a home by up to 80 percent.
  • Keep storm windows up all year.
  • Find a public facility, such as a Library or mall that you can go to during the hottest parts of the day. Some jurisdictions open cooling centers or other places you and your family can go during extreme heat.

Be Safe During a Heat Emergency

During a heat emergency, you can protect you and your family from illness and harm. Ways to be safe include eating well-balanced, light, and regular meals and avoiding salt tablets unless otherwise directed. Drink plenty of water and consult your doctor if you have medical fluid retention issues. Limit your intake of alcoholic beverages; they raise your body temperature. Dress in baggy, lightweight, and light-colored clothes that cover as much skin as possible. Protect your face and head by wearing a wide-brimmed hat. Use sunscreen on exposed skin if you have to be outside. Avoid hard physical work during the warmest part of the day. If you have work to do, use a buddy system and take frequent breaks.

In Your Home

  • Stay indoors as much as possible and limit exposure to the sun.
  • Stay on the lowest floor out of the sun if air conditioning is not available. Heat rises.
  • If you do not have air conditioning, spend the warmest part of the day in public buildings (libraries, schools, malls, etc.) or in designated cooling facilities.

In Your Car

  • Never leave children or pets alone in closed vehicles. Poor air quality and little to no air circulation means that, even with the windows down, your children or pets will be in danger of heat related illness.

Take Action After a Heat Emergency

During and after extreme heat events, remember to check up on family, friends, and neighbors who are alone and do not have air conditioning. If you are 65 years of age or older, have a friend or relative call to check on you twice a day during a heat wave. If you know anyone in this age group, check on them at least twice a day. After extreme heat conditions, it is still likely to be very warm. Continue to hydrate and protect yourself and your family from heat-related illness.

Extreme Heat Key Terms
Excessive Heat Outlook
An excessive heat outlook is issued when the potential exists for an excessive heat event in the next 3-7 days. An outlook provides information to those who need considerable lead time to prepare for the event, such as public utilities, emergency management and public health officials.
Excessive Heat Watch
An excessive heat watch is issued when conditions are favorable for an excessive heat event in the next 12 to 48 hours. This means that the risk of a heat wave has increased, but its occurrence and timing is still uncertain. A watch provides enough lead time so those who need to prepare can do so, such as cities that have excessive heat event mitigation plans.
Excessive Heat Warning/Advisory
An excessive heat warning or advisory is issued when an excessive heat event is occurring, is imminent, or has a very high probability of occurring in the upcoming 36 hours. The warning is used for conditions posing a threat to life or property. An advisory is for less serious conditions that cause significant discomfort or inconvenience and, if caution is not taken, could lead to a threat to life and/or property.

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