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Keeping cool in the heat

Extreme heat can be dangerous to health, and even fatal. We want our residents and visitors to be safe during hot weather. You can find tips and resources on this website.

Signing up for Alert Boston is a great way for residents, businesses, and visitors to be notified in the event of an emergency. If the City of Boston declares an extreme heat event, you will receive a direct message via text, call, or email.

Cooling Resources

Emergency tips and facts

Extreme heat can be dangerous to health by itself. It can also make pre-existing health issues worse. Some areas in the City are hotter due to elevation, limited shade from trees, and heat-retaining structures, like buildings and roads. We have a list of heat safety tips and facts below.

View tips and facts

Never leave children and pets alone in cars. Cars heat up quickly even if the windows are slightly open.

  • If you see an animal locked in a car on a hot day, find the owner as soon as possible. If you can't find the owner, call 911 or contact Animal Care and Control.
  • When leaving your car, check to be sure everyone is out. Don't forget about sleeping children.
  • Keep a stuffed animal in your car seat to remind yourself when a child is in the car. When the child is buckled in, place the stuffed animal in front with the driver. 

Drink more water no matter how active you are. Avoid alcohol and sugary or caffeinated drinks. Don't wait until you're thirsty to drink.

Warning: If your doctor limits the amount of fluid you drink or has you on water pills, ask how much you should drink when it's hot.


Please call your utility company to report any outages. You can also call 3-1-1 with any concerns or questions.


Boston Centers for Youth & Families (BCYF) community centers become cooling centers during periods of extreme heat. Anyone can cool off inside with air conditioning. Check our updated list of cooling centers.

Due to COVID-19, all visitors will be asked to sign in with their name and contact information. They must wear a face covering (covering both the nose and mouth). Visitors must bring their own water and limit their belongings to one small bag.

  • Use child window guards in addition to screens on any open window on the second story or above. 
  • Install window air conditioners securely and insulate if necessary.
  • Check air-conditioning ducts for proper insulation.
  • Reflect heat back outside by installing temporary window reflectors between windows and drapes, such aluminum foil-covered cardboard.
  • 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 entering a home by up to 80 percent.
  • Keep storm windows up all year.

Limit your outdoor activity to morning and evening hours.

  • If you become lightheaded, confused, weak or faint, stop all activity and find shade or a cool area to rest. Call 911 immediately if your symptoms don't improve.
  • Use a buddy system when working outside.
  • Let your body acclimate to the heat before you try to exercise.

Know the difference between different heat related illnesses: 

Heat Cramps: 
  • Heavy sweating during intense exercise
  • Muscle pain or spasms
Heat Exhaustion:
  • Heavy sweating
  • Cold, pale, and clammy skin
  • Fast, weak pulse
  • Nausea or vomiting
  • Muscle cramps
  • Tiredness or weakness
  • Dizziness
  • Headache
  • Fainting (passing out)
Heat Stroke
  • High body temperature (103°F or higher)
  • Hot, red, dry, or damp skin
  • Fast, strong pulse
  • Headache
  • Dizziness
  • Nausea
  • Confusion
  • Losing consciousness (passing out)

Warning signs and symptoms

A few hours in air conditioning can help your body recover and stay cool when you go back into the heat. Electric fans will not prevent heat-related illness.

  • Stay indoors and in an air-conditioned place if possible.
  • If your home doesn't have air conditioning, go to a shopping mall or public library.
  • Take a cool shower or bath. 
  • Use your stove and oven less to maintain a cooler temperature in your home.
Heat Safety Facts Sheets

You can download Heat Safety Facts Sheets on this page for more specific information for:

  • older residents
  • differently abled residents
  • residents living with chronic illnesses or taking medications, and
  • those experiencing homelessness.

Infants, children, people age 65 and older, and those experiencing homelessness are at greater risk for heat-related illness. Other high-risk people are those who are physically ill or who take certain medications.

  • Visit adults at risk at least twice a day and watch them for signs of heat exhaustion or heat stroke. Watch infants and young children often.
  • Plan to check on family, friends, neighbors, and the elderly who do not have air conditioning or who are often alone. 
  • Contact the Age Strong Commission at 617-635-4366 or 3-1-1 for after-hours help.
  • If you observe someone who appears passed out, call 9-1-1 immediately. 
Heat Safety Facts Sheets

You can download Heat Safety Facts Sheets on this page for more specific information for:

  • older residents
  • differently abled residents
  • residents living with chronic illnesses or taking medications, and
  • those experiencing homelessness.

Adults and children should use sunscreen containing an SPF-15 or higher and wear protective, loose-fitting clothing, including long-sleeve shirts and hats.

Multilingual fact sheets

Long periods of hot weather affect people differently, and they can have different effects on a person’s health. The Office of Public Health Preparedness at the Boston Public Health Commission developed a series of fact sheets for residents. The fact sheets below have been translated into the 10 most commonly spoken languages in Boston.

Download Multilingual Fact sheets

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