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Preparedness

Heat and cooling

Last reviewed: 10 November 2026

How a household in Charleston, Dorchester, or Berkeley County can stay safer in high heat when the power is out, recognize heat illness, and keep warm during an uncommon cold-weather outage.

For a household in Charleston, Dorchester, or Berkeley County, heat is the climate problem you are most likely to face in an emergency. After a hurricane or a summer outage, the air conditioning may be off for days while humidity stays high.

When the air conditioning is out

  • Spend time in the coolest room you have, often a lower floor or a shaded interior room.
  • Close blinds or curtains on sun-facing windows during the day. If nights are cooler and the air is not smoky or contaminated, open windows to vent the house, then close them again in the morning.
  • Use battery or USB fans if you have the power for them. A fan does not replace hydration, and in very high heat a fan aimed at a person may not prevent heat illness — it is a comfort tool, not a guarantee.
  • Drink water throughout the day, more than you think you need. See Water. Go easy on alcohol, heavy caffeine, and very sugary drinks.
  • Wear light, loose clothing. Limit outdoor work to early morning or evening, and take frequent shade breaks.
  • Check on older neighbors, very young children, pregnant people, and anyone with heart, lung, or kidney conditions, or who takes medicines that affect heat tolerance.
  • Never leave a person or a pet in a parked car.

If officials open a cooling center, or if a public building with power is available and it is safe to travel, use it during the hottest hours — especially for anyone at higher risk.

Keep medicines stored at the temperatures on their labels. Some drugs fail in heat, and some conditions become more dangerous in it. Ask a pharmacist before storm season if you are unsure.

Heat exhaustion and heat stroke

Heat exhaustion can look like heavy sweating, cramps, tiredness, dizziness, headache, nausea, or a rapid pulse. Move the person to a cooler place, loosen clothing, give small sips of water if they are awake and able to drink, and cool the skin with damp cloths or a spray and airflow. Stay with them.

Heat stroke is a medical emergency. Warning signs can include a very high body temperature, hot skin that may be dry or just not improving, confusion, fainting, a seizure, or rapid breathing or pulse. Call 911. While you wait, get the person out of the heat and cool them by whatever safe means you have (cool water on the skin, ice packs wrapped in cloth at the neck, armpits, or groin) and do not give fluids if they cannot swallow or are unconscious.

These are general first-aid points, not a substitute for official medical advice. When you are unsure, call 911.

Keeping warm when the heat is off

Cold snaps and the occasional winter storm do reach the Lowcountry. If the furnace is electric, or if the power is out, the house can cool quickly.

  • Close off unused rooms. Hang blankets over doorways if you need to keep one room warmer.
  • Dress in layers, including a hat and warm socks. Sleep under extra blankets or sleeping bags — one per person in the house, plus spares in the go-bag.
  • A foil emergency blanket can help hold body heat and is light enough to keep in a car or bag. It is a supplement to real blankets, not a replacement for them in a long outage.
  • Eat regular meals and stay dry. Wet clothing steals heat.
  • Use only indoor-safe heating devices. Never bring a charcoal grill, camp stove, or generator inside, and never use a gas oven as a heater. Carbon monoxide rules are on the power and lighting page.
  • If the house is dangerously cold and a warming center is open, go there.

Infants, older adults, and people with some chronic conditions are more vulnerable to cold as well as heat. Check on them early.

What to have on hand

For a family of four: extra blankets or sleeping bags for everyone; a way to shade and ventilate the main living room; water well above the 1-gallon-per-day floor if a summer outage is likely; electrolyte drinks or packets if your clinician agrees they are appropriate; a battery or USB fan or two if you can charge them; and weather-appropriate spare clothes in the go-bag, including rain gear.

Sources & further reading