Extreme heat is one of the most significant hazards facing New York City, and New Yorkers are especially vulnerable to extreme heat-related hazards during the summer months. Generally, extreme heat means temperatures that hover 10 degrees or more above the average high temperature, last for prolonged periods of time, and are accompanied by high humidity.
Because NYC is made up of materials like asphalt, concrete, and metal that trap heat, temperatures in NYC can oftentimes be 10 degrees higher than other surrounding areas.
Extreme heat can be deadly! Every year, several hundred New Yorkers die from heat illness, which is preventable. If you have certain health conditions, like heart disease or asthma, you may be more susceptible to heat illness and its impacts. Heat deaths are also more common in neighborhoods without access to trees or parks, which help keep temperatures down.
Notify NYC is the City’s official emergency notification system. Receive free, customizable alerts in 13 different languages for emergencies impacting your neighborhood, including extreme heat, storms, local mass transit disruptions, traffic delays, and more.
Download the free mobile app today or receive notifications in 13 different languages by signing up at NYC.gov/notify, following us on Twitter at @NotifyNYC (or @NNYCSpanish, @NNYCChinese, @NNYCArabic, @NNYCBengali, @NNYCChinese, @NNYCCreole, @NNYCFrench, @NNYCItalian, @NNYCKorean, @NNYCPolish, @NNYCSpanish, @NNYCRussian, @NNYCUrdu, @NNYCYiddish) or calling 3-1-1 (212-639-9675 for Video Relay Service, or TTY: 212-504-4115).
Our Ready NY: My Emergency Plan guide is here to walk you through making a plan for extreme heat that meets you and your family's needs. Some tips to consider while making your plan:
Listen to local weather forecasts and announcements from officials. NYC Emergency Management will send emergency alerts and updates to New Yorkers through various channels, including NotifyNYC, the City’s official, free emergency communications program. Learn more and sign up for Notify NYC at NYC.gov/NotifyNYC.
In New York City, most heat-related deaths occur after exposure to heat in homes without air conditioners. Air conditioning is the best way to stay safe and healthy when it is hot outside, but some vulnerable people do not have an air conditioner or do not turn it on when they need it. Encourage vulnerable family, friends, and neighbors to use air conditioning. Help them get to an air-conditioned place if they cannot stay cool at home. Make sure they are drinking enough water.
Check on your neighbors virtually or over the phone during a heat wave, especially if they are older adults, young children, and people with disabilities and access and functional needs. Keep in touch by phone at least twice a day during heat waves.
Older adults and others who may be sensitive to extreme heat should contact friends, neighbors, or relatives at least twice a day during a heat wave. Many older New Yorkers live alone and could suffer unnecessarily in the heat because they are isolated from friends and family.
Protect your pets and service animals when extreme heat strikes:
Use an air conditioner during hot weather and heat emergencies, even if it is only for a few hours. A setting of 78 degrees F (or low cool) can provide a comfortable environment, help save on electricity bills, and conserve energy.
If you have asthma or other respiratory problems, stay in an area where it is cool and the air is filtered or air-conditioned.
If you do not have an air conditioner, or if you struggle to pay for air conditioning, you may qualify for energy assistance. Visit the Human Resource Administration online for information about the Home Energy Assistance Program (HEAP).
During heat emergencies, the City will open cooling centers throughout the five boroughs. Visit the Cooling Center Finder or call 311 (212-639-9675 for Video Relay Service, or TTY: 212-504-4115) to find out whether a cooling center is open near you.
Note: Cooling centers are facilities managed by agency partners who determine each site's hours of operation, level(s) of accessibility and other logistical details. Call ahead to determine whether pets are allowed at the facility. Service animals are always allowed. For additional information, please contact these facilities directly.
If possible, stay out of the sun. When in the sun, wear sunscreen (at least SPF 15) and a hat to protect your face and head. Wear lightweight, light-colored, loose clothing that covers as much of your skin as possible.
If you do not have an air conditioner, keep rooms well-ventilated with open windows and fans. Fans work best at night, when they can bring in cooler air from outside.
Drink fluids — particularly water — even if you do not feel thirsty. (People with heart, kidney or liver disease, or on fluid restricted diets should check with their doctors before increasing fluid intake.)
Avoid strenuous activity, especially during the sun's peak hours – 11 a.m. to 4 p.m. If you must engage in strenuous activity, do it during the coolest part of the day, usually in the morning between 4 a.m. and 7 a.m.
Cool showers or baths may be helpful, but avoid extreme temperature changes. Never take a shower immediately after becoming overheated – extreme temperature changes may make you ill, nauseated, or dizzy.
For more information, visit NYC.gov/health.
The improper opening of fire hydrants wastes 1,000 gallons of water per minute, causes flooding on city streets, and can lower water pressure to dangerous levels and hamper the ability of FDNY to fight fire safely and quickly.
Properly used "spray caps" reduce hydrant output to a safe 25 gallons per minute while still providing relief from the heat. To obtain a spray cap, an adult 18 years or older with proper identification can go to their local firehouse and request one. Learn more from FDNY.
Power outages can happen during hot, humid summer months when people are using a lot of electricity. It is important to save as much energy as possible on these days.
Steps you can take to prevent an outage include:
Certain medical conditions are more susceptible to heat illness:
If you have one or more of these conditions, take steps to ensure that you have access to air conditioning, which can lessen your risk of severe heat illness.
Identify locations in your neighborhood where you can go to beat the heat, like stores or shopping centers with air conditioning, movie theaters, libraries, or pools.
There are two main types of heat illness: heat exhaustion and heat stroke. Heat stroke can be fatal. Call 911 if you are experiencing the following symptoms of potentially deadly heat stroke:
Heat exhaustion has the following symptoms:
If you or someone you know is experiencing heat exhaustion, move to a cool place, ideally someplace with air conditioning. Remove extra clothing and drink lots of water. If symptoms continue, call 911.
Learn more about heat illness and what to do at the NYC Department of Health and Mental Hygiene's website.
The City works closely with the National Weather Service to monitor severe weather threats that could affect the five boroughs. The City uses several forms of outreach to alert the public in an emergency, including Notify NYC, the City of New York's official emergency communications program. The City also shares information with service providers who opt in through the Advance Warning System.
During periods of extreme heat, when the heat index is predicted to be dangerously high, New York City opens cooling centers. Cooling centers are air-conditioned spaces, such as older adult centers, community centers, public libraries, and other public facilities that typically operate during daytime hours and are free and open to the public.
Additionally, the NYC Fire Department (FDNY) and NYC Department of Environmental Protection (DEP) may distribute hydrant spray caps to conserve water. Opening hydrants without a cap results in a drop in local water pressure and threatens firefighting capabilities.
When a heat advisories are in effect, the City installs spray caps on fire hydrants on certain NYC Department of Transportation's (DOT) Open Streets with dense tree canopy cover. Open Streets with cooling features are also called "Cool Streets."
Cool It! NYC is a citywide plan to increase the amount of cooling features available to the public during heat emergencies, particularly in neighborhoods that face the dangers of high heat. Learn more about Cool It! NYC and find places near you to hydrate, refresh, and stay in the shade from NYC Parks.