Staying safe in a heat wave
Drink water before you’re thirsty, stay in air conditioning, avoid the hottest hours and wear light clothes. Without AC, go to a cooling center; fans may not be enough. Heat exhaustion means heavy sweating, dizziness, nausea or weakness: move somewhere cool and sip water. Heat stroke means high body temperature, confusion or fainting: call 911. Never leave anyone in a parked car. Check on older neighbors, ask about medicines that raise risk, and look into energy assistance.
Your checklist
- Drink water before you’re thirsty
- Stay in AC or a cooling center
- Avoid the hottest hours
- Heat stroke signs? Call 911
- Never leave anyone in a parked car
- Check on older neighbors
Rather read it? Here’s the whole thing.
Who’s most at risk
Older adults, babies and young children, outdoor workers, people with heart, lung or kidney conditions, people taking certain medicines, and people without air conditioning.
Stay cool
- Drink water regularly, before you feel thirsty. Limit alcohol and very sugary drinks.
- Stay in air conditioning as much as you can.
- Avoid strenuous activity in the hottest part of the day.
- Wear light, loose, light-colored clothing.
- Take cool showers or baths.
Cooling centers
In extreme heat, fans alone may not prevent heat illness. Libraries, malls and city cooling centers can help. Call 211 or check your city’s website.
Warning signs
- Heat exhaustion: heavy sweating, cool clammy skin, dizziness, nausea, headache, weakness. Move somewhere cool, loosen clothing and sip water. Get help if symptoms get worse or last more than an hour.
- Heat stroke: very high body temperature, confusion, slurred speech, fainting, or seizures. Call 911, move the person somewhere cool, and cool them with water or cloths while waiting.
Hot cars
Never leave children, older adults or pets in a parked car, even briefly or with windows cracked.
Check on others
Call or visit older relatives and neighbors twice a day during heat waves. Ask a doctor or pharmacist whether any medicines increase heat risk.
Help with bills
Energy assistance programs in many states help with cooling costs, and utilities may offer payment plans.
Official sources, and where to look
- CDC: extreme heatcdc.gov
- Ready.gov: extreme heatready.gov
- LIHEAP: energy bill helpacf.hhs.gov
[your city] cooling centers[your state] LIHEAP apply
Common questions
Is a fan enough during a heat wave?
In extreme heat, fans may not prevent heat illness. Air conditioning or a cooling center is safer. More ›
What’s the difference between heat exhaustion and heat stroke?
Heat exhaustion is a warning: cool down and hydrate. Heat stroke is an emergency with high body temperature and confusion: call 911. More ›
What are the signs of heat stroke?
Very high body temperature, confusion, slurred speech, fainting or seizures. Call 911 and cool the person while waiting. More ›
What are the signs of heat exhaustion?
Heavy sweating, cool clammy skin, dizziness, nausea, headache and weakness. Move somewhere cool and sip water. More ›
Where can I go to cool off if I don’t have AC?
Cooling centers, libraries and malls. Call 211 or check your city’s website for locations. More ›
Who is most at risk in a heat wave?
Older adults, babies and young children, outdoor workers, people with chronic health conditions, and people without air conditioning. More ›
Know someone who needs this?
Not yet reviewed by an expert. Last checked 2026-10-29. This is general help, not legal, medical or professional advice. Rules are different in every state.