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Heat

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Hazard guide · Heat

Extreme heat

Extreme heat means temperatures above 90°F with high humidity for at least two to three days. It causes more deaths each year than any other weather hazard, and older adults, children and people with chronic conditions are most at risk.

Last reviewed November 4, 2026Based on Ready.gov guidance

Most important

If you suspect heat stroke, call 911 right away.

Before

  • Learn the signs of heat illness (below) so everyone in the house can spot them.
  • Don't count on fans as your main way to stay cool. They move air but don't lower body temperature or prevent heat illness.
  • Find places nearby to cool off, such as libraries, malls or a cooling center your health department lists.
  • Cover windows with drapes or shades, weather-strip doors and windows, and add insulation to keep heat out.
  • Install window air conditioners and insulate around them.
  • If cooling costs are out of reach, the Low Income Home Energy Assistance Program (LIHEAP) can help.

During

  • Never leave people or pets in a closed car on a warm day.
  • No AC at home? Go to a cooling center. Take cool showers or baths and use the oven less.
  • Wear loose, light-colored clothing, drink plenty of fluids, and avoid hard work outside at midday.
  • Check on family, older adults and neighbors. Give pets cool water and shade, and remember hot pavement burns paws.
  • Heat waves can knock out power, so keep the outage plan ready.

After

  • Heat stroke: body temperature above 103°F; red, hot, dry skin; a rapid strong pulse; dizziness or confusion. Call 911, move the person somewhere cool, and put cold wet cloths or ice on the head, neck, armpits and groin.
  • Heat exhaustion or cramps: heavy sweating, paleness, cramps, weakness, nausea. Move somewhere cooler, loosen clothing and sip water or a sports drink. Call a doctor if it gets worse or lasts more than an hour.

In your plan

When you tick heat under "What your area gets", the plan tool adds these to your buying schedule:

  • Shades or blackout curtains for sunny windows
  • A window AC for one room (Better budget)
  • Cooling and power-outage items timed before summer

Build my plan