Stay cool during a summer outage: simple cooling tricks, hydration, heat illness warning signs and when to head for a cooling centre.
- Keep the sun out by day and ventilate at night.
- Cool your body directly and hydrate regularly.
- Know the heat stroke warning signs and call for help.
When a heat wave knocks out the power, the air conditioner, fans and even the water pump may stop. Heat can become dangerous quickly, especially for older adults, babies, pregnant people, outdoor workers, pets and anyone with a chronic health condition. This guide covers practical ways to reduce heat and spot problems early.
It complements our heat wave power outage guide. Heat illness is a medical matter, so follow the guidance of public health authorities and seek help when in doubt.
Keep the heat out first
- Close curtains, blinds or reflective covers on sun-facing windows during the day.
- Keep windows and doors closed while it is hotter outside than inside.
- Open windows at night or in the early morning when the outdoor air cools, and create a cross-breeze if it is safe and secure.
- Avoid using the oven, stove or other heat sources inside.
- Move to the lowest, shadiest part of the house, which is often a basement.
Cool your body directly
Because you cannot cool the whole house, cool yourself. Wear loose, light-coloured clothing. Take cool, not ice-cold, showers or baths. Use a damp cloth on your neck, wrists and face, and wet your clothing or hair. A spray bottle and a battery or rechargeable fan help evaporation work. Rest during the hottest part of the day.
Hydration
Drink water regularly, even if you do not feel thirsty. Avoid alcohol and heavy sugary drinks. Public health agencies warn that people with medical conditions or on fluid restrictions should ask a provider how much to drink. Store enough water for drinking and cooling (see how much water to store), and keep it in a cool place. Eat light meals and choose no-cook options (see no-cook foods).
Know the warning signs
Official guidance describes two stages. Heat exhaustion can include heavy sweating, weakness, headache, nausea, dizziness and cool, clammy skin. Move to a cooler place, loosen clothing, apply cool cloths and sip water. Heat stroke is an emergency: signs include a very high body temperature, hot dry or damp skin, confusion, fainting or seizures. Call emergency services and cool the person while waiting.
Look out for the vulnerable
- Check on older neighbours and relatives at least twice a day (see neighbour check-ins and seniors and older adults).
- Give pets shade, water and a cool surface (see pets in a power outage).
- Do not rely on a fan alone when it is very hot, because fans may not prevent heat illness at extreme temperatures.
Power for fans
A small battery or power station can run a fan for a long time. Fans use modest power compared with an air conditioner, which usually draws far more than most portable units can supply. Check the label, and see what to plug into a power station first and our heat and light hub. Never run a generator indoors or in an attached garage.
Cooling centres and when to leave
Many cities open cooling centres, libraries or air-conditioned public spaces during heat events. Check your municipality's website or alerts (see alerts and outage reporting). Leave home if the indoor temperature climbs, if anyone has symptoms, or if the outage is long. Medications can also be affected by heat, so check the label.
Quick action plan
- Block sun and keep the heat out during the day.
- Cool your body with water, damp cloths and rest.
- Drink water often and eat light foods.
- Check on others, including pets.
- Go to a cooler place if it is not improving.
Prepare before summer
Heat events are often forecast days ahead, so use the time. Fill and freeze water bottles to use as ice and drinking water, wash and dry light clothing, find the coolest room in your home, and charge fans and power banks. Hang reflective sunshades or light curtains where the sun hits hardest. Plan where you could go if the house becomes too hot, including a friend's air-conditioned home or a cooling centre, and know how you would get there. Add these steps to your 72-hour checklist.
Quick answers
Are fans enough in a heat wave?
Fans help move air and evaporate sweat but may not be enough in extreme heat. Use water, shade and a cooler location too.
When should I go to a cooling centre?
Go if your home is getting hotter, someone shows symptoms, or the outage is long. Check local listings.