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Ready Marine Corps

Emergency Preparedness Program

Brought to You By Your Marine Corps Emergency Management Team
Extreme Heat
A Marine struggles while exercising during extreme heat conditions.
Extreme heat
can be very dangerous. In extreme heat and high humidity, evaporation is slowed and the human body must work extra hard to maintain a normal temperature. This can push the body beyond its limits. In the United States each year, 400 people die from heat-related complications, more than from any other natural disaster.

Photo by Lance Cpl. Sean Dennison

How To Prepare
  • Stay informed, and know heat terminology:
    • Heat Wave—An extended period of extreme heat, usually combined with excessive humidity.
    • Heat Index—A number of degrees in Fahrenheit (F) added to the air temperature that tells how hot it feels with the relative humidity.
    • Excessive Heat Watch—Conditions are favorable for an excessive heat event to meet or exceed local Excessive Heat Warning criteria in the next 24 to 72 hours.
    • Excessive Heat Warning—Heat Index values are forecast to meet or exceed locally defined warning criteria for at least two days (daytime highs=105-110° Fahrenheit).
    • Heat Advisory—Heat Index values are forecast to meet locally defined advisory criteria for one to two days (daytime highs=100-105° Fahrenheit).
  • Listen to local weather forecasts and stay aware of upcoming temperature changes.
  • Be aware that people living in urban areas may be at greater risk from the effects of a prolonged heat wave than are people living in rural areas, due to stagnant and poor air quality, as well as stored heat in asphalt and concrete.
  • Make a plan to keep you and your family safe from the effects of extreme heat.
  • Make sure you have a fan, snugly fit window air conditioner, or something to circulate air in extreme heat as many heat-related deaths can be attributed to stagnant atmospheric conditions or poor air quality.
  • Insulate air ducts and weather-strip doors and sills to keep cool air in.
  • Cover windows that receive morning or afternoon sun with drapes, shades, etc.
  • Keep storm windows up year round.
  • Understand that elderly, young, sick, and overweight individuals are at greater risk, and learn first aid to help treat heat-related emergencies.
  • Build an emergency kit.
NOTE: Per MARADMIN 111/15, “Officers, staff noncommissioned officers, noncommissioned officers and other supervisors shall ensure Marines, Sailors, and civilian personnel are familiar with heat and cold stress injury prevention." 

Flag Condition Information

What to Do If There Is Extreme Heat
  • Slow down and don’t do anything too strenuous.
  • Stay inside as much as possible.
  • Never leave children or pets alone in closed vehicles.
  • If air conditioning is not available in your home, stay on the lowest level or go to a public building with air conditioning.
  • If you stay in your home without air conditioning, make sure there is a way, such as a fan, to circulate the air around you.
  • Drink lots of water, even if you don’t feel thirsty.
  • Eat well-balanced, light, and regular meals.
  • Avoid alcohol, caffeine, and salt.
  • Wear loose-fitting, lightweight, and light-colored clothing.
  • Be aware that a power outage or drought can result from a heat wave.
  • Per MARADMIN 111/15, practice buddy aid: "If someone looks ill or otherwise unfit to participate, ensure those individuals report to medical department personnel for assessment." 
Heat Emergencies
  • Keep a lookout for possible heat emergencies:
    • Heat cramps—Muscle spasms and aches from heavy exertion in extreme heat. They are usually the first sign of heat-related complications.
    • Heat exhaustion—A form of mild shock that results from insufficient body fluids due to extreme heat and excessive exercising. The blood flow to the skin increases, decreasing blood flow to vital organs and raising the body temperature, increasing the risk of a heat stroke.
    • Heat stroke/sun stroke—The body’s temperature control system stops working, causing body temperature to rise so high (103˚F or more) that there may be brain damage or death.
  • If you experience or observe any of the above conditions, seek medical attention immediately.
Prepare Pets
Collapse All Expand All
A Marine K-9 is pictured.
150924-M-MS007-013 Photo by Cpl. Thor J. Larson

  1. Limit exercise on hot days to early morning or evening hours. Walk on the grass to keep the pavement from burning your pet’s paws. Bring plenty of water for you and your pet to prevent dehydration.
  2. Provide ample shade when pets are outside. Tarps and tree shade are best because air can circulate. Doghouses trap heat and actually make warm conditions more harmful to pets.
  3. Provide plenty of fresh, cold water. Add ice whenever possible and always keep bowls in the shade.   
  4. Watch for signs of heat stroke. Some signs are heavy panting, glazed eyes, rapid heartbeat, difficulty breathing, excessive thirst, lethargy, lack of coordination, profuse salivation, vomiting, a deep red or purple tongue, seizure, and unconsciousness.
    1. To treat heatstroke: Move your pet into the shade or an air-conditioned area. Apply ice packs or cold towels to the head, neck, and chest or run cool (not cold) water over your pet. Let your pet drink small amounts of cool water or lick ice cubes. Visit a veterinarian immediately.
  5. Prepare for power outages. Extreme heat may cause power outages. Make a plan to keep your pets safe! 

Set your own course through any hazard: stay informed, make a plan, build a kit.
Live Ready Marine Corps.

Where to Find Additional Information

Centers for Disease Control and Prevention

Centers for Disease Control and Prevention

Department of Homeland Security (Ready.gov)www.ready.gov/heat  

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