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How to Stay Safe During Extreme Heat

caution sign The information on this page may be outdated as it was published 3 years ago.

Hot weather and extreme heat can cause serious illness and can even be life-threatening.

During heat waves, Cambridge Police Officers will distribute cold bottles of water to residents in need while they are out on patrol.

What is extreme heat?

Extreme heat is a prolonged period of very hot weather, which may include high humidity. In Massachusetts, a “heat wave” is usually defined as a period of three or more consecutive days above 90ºF (Fahrenheit) or 32.2ºC (Celsius). Click here to learn more about heat-related terms (e.g., heat advisory, heat warning).

How do I stay safe and cool during extreme heat?

  • Know the signs of heat-related illnesses.
    • Headaches, dizziness, nausea, confusion, cramps, high body temperature, or a fast pulse are among the signs of heat-related illness.
    • If you are experiencing any of these symptoms, seek medical help immediately and move to a cooler place.  Learn more.
  • Stay hydrated.
    • Keep drinking water, even if you don't feel like it. Drink two to four glasses of cool fluids every hour.
    • Avoid alcoholic drinks and too much caffeine and sugar.
    • Bring water with you wherever you go outside. Public water fountains and water refill stations are open in City parks.
  • Stay cool outdoors.
    • Limit outdoor activities to mornings and evenings when it is cooler. Be sure to decrease your overall level of physical exertion.
    • Protect yourself from the sun. Use sunscreen that is SPF 15 or higher and look for those that say “broad spectrum” or “UVA/UVB protection” on their labels.
    • Wear loose-fitting and light-colored clothing to keep cool. You can also wear a hat and sunglasses.
    • Place an extra handkerchief or neck gaiter into cold water. Wring it out so it is not dripping. Place or tie it around your neck. Repeat throughout the day.
    • Seek shade
    • Find Pools & Waterplay Features in Cambridge
      • Visit a sprinkler or spray park. Find one near you on the City's Waterplay Map
      • Visit a public pool. You can find local State-run pools and information about their hours here.
  • Stay cool indoors.
    • Close windows and blinds during the day.
    • Take cool showers.
    • Use air conditioning or fans. However, when the temperature is in the high 90s (or higher than 32.2ºC), fans will not prevent heat-related illnesses. If you are concerned about the cost of running your air conditioner, check to see if you are eligible to receive a discounted electricity rate from Eversource to help lower your electricity bills.
    • Stay cool by spending time in air-conditioned places like the mall, movie theater, and public libraries. View public library locations and hours.
    Be a good neighbor. Be sure to check on neighbors, especially the elderly, and people who live alone, have medical conditions, may need additional assistance, or don't have air conditioning. 
  • Children and pets should not be left in cars.
    • Never leave children or pets in a car unattended, even if running out for curbside pickup or other quick errands. Interior temperatures can rise almost 20°F within 10 minutes even with the windows cracked open.
  • Call 911 in an emergency.
    • If you or someone is showing signs of heat stroke call 911 immediately. Signs of heat stroke include:
      • A body temperature over 103 degrees; hot, red, dry, or moist skin; a rapid and strong pulse; and possible unconsciousness.
      • While waiting for help to arrive, move the person into a cool area, help cool them down with wet towels or a cool bath, and DO NOT give them fluids.

What are the signs of heat-related illness?

Heat-related illness comes in many forms, including heat exhaustion, heat stroke, heat cramps, and more. Know the signs of heat-related illnesses so that you can take care of yourself or others as needed. Some of these heat-related illnesses can be fatal and medical attention is important. To learn more about heat-related illnesses, what you can do, and when to seek medical attention, click here.

Who is at risk for heat-related illnesses?

While everyone is at risk for heat-related illness, some people are at greater risk and should take special precautions. These populations include:

  • People 65 and older, children younger than two, and people with pre-existing medical conditions such as cardiovascular disease, diabetes, or respiratory illness are at greatest risk for heat-related illness;
  • People who work outside or spend a lot of time outdoors such as athletes;
  • People who may be socially isolated, including individuals experiencing homelessness and elderly residents;
  • People taking certain medications. Be sure to consult a doctor about the medications you are taking and extreme heat;
  • Those who are overweight and obese; and
  • People who are pregnant. 

How can I protect family, friends, and neighbors?

  • Never leave children or pets in cars, even for a few seconds. Cars can heat up to dangerous temperatures in a very short time, even with the windows open. Make sure your loved ones drink plenty of water and stay hydrated throughout the day, including pets.
  • Connect with elderly neighbors and others at risk during a heat wave.  
  • Young children and people with chronic health conditions should also be monitored for heat-related illnesses.
  • Call 911 if you see someone with signs of heat stroke or clearly in need of medical assistance.

What should I do to prepare for, and help prevent, power outages?

  • Plan ahead. Have supplies in case there is a power outage including batteries, flashlights, and nonperishable food.
  • If you have life-support devices, such as home dialysis, breathing machines, or other medical equipment or supplies, that depend on electricity:
    • Talk to your health care provider about how to use them during a power outage;
    • Contact your local electric company and equipment suppliers about your power needs. Some utility companies will put you on a "priority reconnection service" list;
    • Let the fire department know that you are dependent on life-support devices; and
    • If you have medication that requires refrigeration, check with your pharmacist for guidance on proper storage during an extended outage.
  • Monitor the weather. Watch your local news or visit National Weather Service–Boston for advisories and alerts.
  • If there are advisories and alerts, fully charge your cell phone, laptop, and other electronic devices in case there is a power outage.
  • Conserve as much energy as possible to avoid power disruptions. Turn off all nonessential appliances and lights in unoccupied rooms.

What should I do during a power outage?

  • Check current power outages in the state with the Power Outage Map by Massachusetts Emergency Management Agency.
  • Call your utility company to report power outages and learn when your power will be restored. Do not call 9-1-1 to report an outage or to ask about power restoration.
  • Stay away from downed utility wires. Always assume a downed power line is live. Call 9-1-1 to report emergencies including downed power lines or if you are dependent on equipment that requires electricity and you need medical assistance.
  • Make sure you and your loved ones stay hydrated.
  • Keep refrigerator and freezer doors closed. An unopened refrigerator will keep food cold for about four hours. A full freezer will keep the temperature for about 48 hours
  • If possible, use flashlights instead of candles. If you must use candles, place them in safe holders away from anything that could catch fire. Never leave a burning candle unattended.
  • Learn more about power outages at the state’s website. 

What are some of the heat-related terms that I should know?

  • Heat Index: A measure of how hot it really feels when relative humidity is factored in with the actual air temperature. Learn more.
  • Excessive Heat Watch: Weather conditions are favorable for an excessive heat warning in the next 24 to 72 hours.
  • Heat Advisory: Daytime heat indices (plural of index) of 100ºF–104ºF (37.8ºC–40.0ºC) for two or more hours.
  • Excessive Heat Warning: Daytime heat indices of greater than or equal to 105°F (40.6ºC) for two or more hours.

Additional Resource Links


Page was posted on 6/7/2021 3:37 PM
Page was last modified on 7/26/2023 2:36 PM
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