Ready Now Project

How to stay cool without power in a heat wave

Get to air conditioning if you can, even for a few hours: a cooling center, library, or shopping mall. Dial 2-1-1 to find one. At home, take cool showers or baths, wear loose, light-colored clothing, drink plenty of fluids, and do not rely on a fan once it is above 90°F indoors.

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Heat can knock out power, and a heat wave without air conditioning is dangerous. CDC says “Heat can cause power outages,” and advises having a plan for refrigerated medications and electronic medical devices. This page covers how to cool down, who to check on first, and how to recognize heat illness.

Get to air conditioning

You do not need air conditioning at home to get the benefit of it.

  • Find a cooling location. CDC says to find a location with air conditioning by dialing 2-1-1, and that local health departments and emergency management agencies can point you to cooling centers. Ready.gov says to identify places such as libraries and shopping malls, and if air conditioning is not available at home, to find a cooling center.
  • A few hours helps. CDC’s power outage guidance says even a few hours spent in air conditioning at a shopping mall or public library can help.
  • Leave if you need to. CDC says that if conditions are too hot, seek shelter with friends or at a community shelter. Ready.gov says to go to a community location with power if heat is extreme.

If you have or are planning backup power, see home backup power, how big a portable power station you need, and, for generators, generator safety.

Staying cool at home without power

From Ready.gov, CDC, and CDC’s power outage page:

  • Take cool showers or baths.
  • Wear loose, lightweight, light-colored clothing.
  • Avoid using the stove or oven, which heats the house.
  • Drink plenty of fluids to stay hydrated.
  • If you go outside, find shade and wear a hat wide enough to protect your face.

When a fan stops helping

Ready.gov says not to rely on a fan as your primary cooling device: fans create air flow and a false sense of comfort, but do not reduce body temperature or prevent heat-related illness.

Who is at highest risk in a heat wave

CDC lists these groups at increased risk for heat-related illness:

  • Older adults (aged 65 and older)
  • Infants and children
  • People with chronic conditions
  • People without air conditioning
  • Pregnant people
  • Outdoor workers and athletes

CDC also names people with asthma or heart disease. For older adults, CDC explains that they do not adjust as well as young people to sudden temperature changes, and are more likely to take prescription medicines that affect the body’s ability to control its temperature or sweat.

Heat stroke: signs and what to do

Heat stroke is a medical emergency. CDC’s heat-related illness guide lists these signs:

  • High body temperature (103°F or higher)
  • Hot, red, dry, or damp skin
  • Fast, strong pulse
  • Headache, dizziness, nausea
  • Confusion
  • Losing consciousness (passing out)

Ready.gov adds: remove outer clothing, and place a cold, wet cloth or ice pack on the head, neck, armpits, and groin, or soak the person’s clothing with cool water.

Heat exhaustion: signs and what to do

Signs, per CDC:

  • Heavy sweating
  • Cold, pale, and clammy skin
  • Fast, weak pulse
  • Nausea or vomiting
  • Muscle cramps
  • Tiredness or weakness
  • Dizziness, headache, fainting

What to do:

  1. Move to a cool place.
  2. Loosen clothes.
  3. Put cool, wet cloths on the body or take a cool bath.
  4. Sip water.

Get medical help right away if the person is throwing up, if symptoms get worse, or if symptoms last longer than 1 hour.

Heat cramps

Heat cramps are muscle pain or spasms with heavy sweating during intense exercise. CDC says to stop physical activity, move to a cool place, drink water or a sports drink, and wait for the cramps to go away before doing more. Get medical help right away if cramps last longer than 1 hour, or if the person is on a low-sodium diet or has heart problems.

Medicines and medical devices in the heat

Because heat can cause power outages, CDC advises a plan for refrigerated medicines and powered medical devices before the heat arrives. See medical needs in an outage and the medicine section of what to do when the power goes out.

Heat wave outage checklist

Before summer

During a heat wave outage

Heat illness