How to Prepare for a Heatwave: A Calm Safety Guide
Extreme heat is the quiet hazard — it kills more people in many countries than storms or floods, yet it arrives without the drama. The good news: heat is one of the most *surv
Extreme heat is the quiet hazard — it kills more people in many countries than storms or floods, yet it arrives without the drama. The good news: heat is one of the most *survivable* emergencies if you know a few calm basics. And the dangerous combination — a heatwave plus a power cut that kills the air-conditioning — is exactly the kind of thing worth thinking through before it happens.
Here's the practical, no-panic guide, based on guidance from the CDC and FEMA's Ready.gov.
The quick version
- Stay cool: air-conditioning is the single best protection. No AC? Find a cooling centre (library, mall).
- Hydrate — drink water regularly, *before* you feel thirsty.
- Know the signs: heat exhaustion (cool down, rest, water) vs heat stroke (call 911 / emergency — it's life-threatening).
- Never leave a child, older adult, or pet in a parked car — even "for a minute."
1. Stay cool — the one thing that matters most
Your body copes with heat mainly by sweating. When it can't keep up, illness follows. So the priority is simple: stay cool.
- Air-conditioning is the strongest protection. Spend the hottest hours somewhere cool.
- No AC at home? Identify a cooling centre in advance — a library, shopping centre, or a place your local authority opens during heat alerts. A few hours in AC during peak heat resets your body.
- Fans help, but in extreme heat a fan alone isn't enough — once air temperature is very high, a fan just moves hot air. Pair it with cool showers and shade.
- Limit exertion during the hottest part of the day (late morning to evening). Reschedule hard tasks to early morning.
- Wear loose, lightweight, light-coloured clothing; close blinds/curtains on the sunny side by day.
2. Hydrate — before you feel thirsty
- Drink water regularly throughout the day — don't wait until you're thirsty (CDC).
- Go easy on alcohol and very sugary drinks — they work against hydration.
- If you sweat heavily for hours, add some salty food or an electrolyte drink.
3. Know the signs — heat exhaustion vs heat stroke
This is the section to read twice, because telling them apart changes what you do.
Heat exhaustion (serious, but you can manage it):
- Heavy sweating, cold or clammy skin, a fast/weak pulse
- Feeling weak, dizzy, nauseous, thirsty, or uncoordinated
- What to do: move to a cool place, sit/lie down, loosen clothing, sip water, cool the skin (damp cloth, cool shower). If it worsens or there's vomiting, get medical help.
Heat stroke (a medical emergency — life-threatening):
- Body temperature 103°F (39.4°C) or higher
- Hot skin that may be red and dry or damp; throbbing headache; confusion or slurred speech; rapid strong pulse; fainting or loss of consciousness
- What to do: call 911 (or your local emergency number) immediately. While you wait, move the person somewhere cool and cool them fast — damp cloths, fan, cool water on skin. Do not give fluids to someone who is confused or unconscious (CDC).
Heat stroke can raise body temperature to dangerous levels within 10–15 minutes and cause permanent harm or death without emergency care. When in doubt, treat it as an emergency.
Want a calm, personal readiness check? The free Resilience Score takes about three minutes and flags your gaps — including heat, water and power. → Take the Resilience Score
4. Never leave anyone in a parked car
A parked car becomes lethally hot in minutes, even with a window cracked, even on a "mild" warm day. Never leave a child, an older adult, or a pet in a parked car — not even for a moment. Make it an absolute household rule.
5. Protect the people most at risk
Heat hits some people much harder. Check on them often during a heatwave:
- Older adults (especially living alone) and infants/young children
- People with heart, lung, kidney, or mental-health conditions, or on certain medications
- Outdoor workers and athletes
- Anyone without air-conditioning
A quick daily call or visit to an elderly relative or neighbour during a heat alert genuinely saves lives.
6. If the power goes out during a heatwave
This is the dangerous combination — no AC, no fans, food spoiling fast. A calm plan:
- Know your cooling centre (Section 1) — leave for it early if the home gets too hot.
- Keep water frozen in bottles ahead of a heat alert — they cool a room, a cooler, and you.
- Keep the fridge/freezer closed (see our power-outage checklist) and a few days of water stored (see emergency water storage).
- A power bank keeps your phone alive for heat alerts and check-ins.
(Winter has the opposite failure mode — see the winter power outage guide.)
7. Prep your home before the heat
- Identify the coolest room (often north-facing, ground floor) and plan to gather there.
- External shade (blinds, awnings, even a sheet over a sunny window) beats internal curtains.
- Freeze water bottles and make ice in advance.
- Make sure your emergency kit is stocked (kit checklist).
Your heatwave checklist
- [ ] A cool place identified (home AC or a cooling centre)
- [ ] Water stored + bottles frozen ahead of the alert
- [ ] Plan to check on elderly/infant/at-risk people daily
- [ ] Everyone knows heat-stroke signs = call 911
- [ ] Absolute rule: no one and no pet left in a parked car
- [ ] Blinds/shade on sunny side; coolest room identified
- [ ] Power bank charged (in case AC/grid fails)
Frequently asked questions
What are the warning signs of heat stroke?
Body temperature 103°F (39.4°C) or higher, hot red or damp skin, confusion or slurred speech, throbbing headache, rapid pulse, fainting. It's a medical emergency — call 911 (CDC).
What's the difference between heat exhaustion and heat stroke?
Heat exhaustion has heavy sweating, cool/clammy skin and weakness — cool down and hydrate. Heat stroke has very high body temperature, confusion and possibly dry skin — it's life-threatening, so call emergency services immediately.
How much water should I drink in a heatwave?
Drink regularly through the day rather than waiting until thirsty; more if you're active or sweating. Ease off alcohol and sugary drinks.
What if I don't have air-conditioning?
Find a cooling centre (library, mall, or one your local authority opens), use cool showers, freeze water bottles, shade windows, and limit exertion during peak heat.
Heat is just one scenario — pair this with a power-outage plan, water supply, an emergency kit, and its winter counterpart, the winter power outage guide. To see your home's gaps in three minutes, take the free Resilience Score.