Extreme heat preparedness: stay cool when the power goes out

Make access to cooling the first decision

Before a heat wave, identify an air-conditioned place you can reach if home cooling fails. Contact local emergency management or public health for cooling options. Charge your phone and arrange transport before the hottest part of the day. CDC heat guidance.

A practical plan needs a primary destination and a fallback, not just “go somewhere cool.” Confirm opening hours, step-free access, transport, pet rules and overnight arrangements. A center that closes at 6 p.m. does not solve a hot overnight outage. New York’s cooling-center guidance shows why access and operating arrangements matter.

Use the forecast to prepare earlier

Check local heat alerts and the NWS HeatRisk forecast. HeatRisk considers how unusual the heat is for the place and season, its duration and daytime and overnight conditions. It is broader context, not a personal medical clearance. See NWS’s HeatRisk explanation.

Record the hours when travel and necessary outdoor work are likely to be less hot. Check air quality too: an open-window plan may fail when smoke is present. Our local forecast tool can help with timing, while official warnings and personal health needs govern decisions.

Set an early action point with anyone who needs help. “We will confirm the ride this morning and leave while the destination is open” is a useful household arrangement. Waiting until someone feels seriously ill leaves less room to solve a failed ride, closed facility or inaccessible entrance.

Reduce indoor heat, and understand the limits of fans

Shade sun-facing windows and reduce indoor heat from cooking and other appliances. When outdoor air is hotter, keep windows closed; consider opening them when it is cooler only if outdoor air quality, security and local advice allow. Maintain cooling equipment before hot weather. EPA indoor heat guidance.

CDC advises using fans only when indoor temperature is below 90°F (about 32°C). Above that, a fan can raise body temperature. A fan moves air; it does not cool the room like air conditioning. The threshold is not a declaration that 89°F is safe: health, humidity, duration and symptoms can require earlier action. CDC fan guidance.

Cool showers and damp cloths can support cooling. They do not make a dangerously hot home a reliable shelter. If the room is becoming too hot or someone is struggling, use the planned air-conditioned destination. A battery fan must never become the reason to postpone needed cooling or medical help.

Prepare for the outage before it starts

This table is an editorial worksheet. Fill it with actual names and places, then call to confirm them. A destination can be affected by the same outage, so verify it is operating before travel when possible.

A small USB bank cannot power a household air conditioner. Even a larger battery needs both sufficient energy and compatible continuous and startup output. As an illustrative calculation, a 1,000 Wh battery at an assumed 85% usable fraction supplying a constant 800 W load would last about 1.06 hours. This is not a claim about a particular AC or battery; real cycling, surge and losses vary. Use the runtime calculator only after checking compatibility.

Keep generators outdoors, at least 20 feet from doors, windows and vents. Never run one in a garage or shed. A carbon monoxide alarm does not make unsafe placement acceptable. CDC generator safety.

Plan around people, medicines and pets

Older adults may be less able to adjust to heat and may have medical conditions or medicines that increase risk. For someone in your care, check at least twice daily and verify that cooling is actually available. Ask about symptoms, access to drinks and a way to leave; a brief text reply alone may not answer those questions. CDC older-adult guidance.

Include infants, young children, pregnant people, people living alone and those with chronic conditions or access needs. Ask a clinician or pharmacist for a heat plan if fluid restrictions, diuretics, refrigerated medicines or powered equipment are involved. Do not stop or change medicines on your own. CDC medicine and heat guidance.

Keep drinking water accessible and refill a carrying bottle. Do not apply one fluid quantity to every person; medical restrictions need individualized advice. Never leave a person or animal in a parked vehicle, even briefly. Pets need water, shade and a cool destination too. NWS heat-wave safety.

Recognize heat illness and act

Heat illness can worsen quickly. Sweating does not rule out heat stroke, and a home thermometer is not needed to recognize a medical emergency. The following actions follow NWS heat-illness guidance.

Possible heat exhaustion

Signs: Heavy sweating, weakness, headache, dizziness, nausea or clammy skin.

What to do: Move to an air-conditioned place, loosen clothing and use cool wet cloths. Offer small sips of water only if fully alert and able to swallow. Seek immediate medical help for vomiting, worsening symptoms or symptoms lasting over an hour.

Possible heat stroke

Signs: Confusion, slurred speech, seizures, collapse or loss of consciousness. Skin may be wet or dry.

What to do: Call emergency services immediately. Move to a cooler place if safe and start rapid cooling with cool water and wet cloths while following dispatcher instructions. Do not give fluids to someone with suspected heat stroke.

Do not leave an ill person alone to go shopping for equipment. If you are unsure whether symptoms are serious, seek medical help. CDC/NIOSH heat-illness information provides additional warning signs.

Buy for a specific gap in the plan

A battery-powered room thermometer helps you notice a rising temperature during an outage. It does not diagnose heat illness or establish that remaining at home is safe. Our researched example, the AcuRite 00613, has manufacturer-stated ±2°F accuracy: a reading near a decision point should not be treated as exact. Keep it in a representative indoor position according to its instructions, away from misleading local heat sources.

A refillable bottle supports the trip to a cooling destination. The Nalgene example below is a carrying container, not a filter, insulated bottle or full household reserve. An existing clean bottle may serve perfectly well. Ordinary clean cloths, suitable clothing and a tested phone charger can also come from supplies you already own.

These are function-based recommendations from manufacturer documentation, not comparative lab tests. We have not added electrolyte powders, a new air conditioner or a large power station as default purchases. The right equipment follows from the person, building and cooling plan.

Rehearse the plan while it is still comfortable

1. Confirm two cool destinations and whether either can support an overnight stay.
2. Test the route and accessible transport arrangements.
3. Pack medicines, contact details, charging cable, water and pet supplies.
4. Agree who checks on each person and what to do if they do not answer.
5. Check household cooling, indoor temperature monitoring and official warnings.
6. After the event, recharge equipment and record any failed transport or access arrangements.

Keep the essentials in your household plan. For a brief recap use the extreme heat field guide; for food during an outage read the refrigerator thermometer guide.