About Heat Waves


In recent years, excessive heat has caused more deaths than all other weather events, including floods.  A heat wave is a prolonged period of excessive heat, generally 10 degrees or more above average, often combined with excessive humidity.

You will likely hear weather forecasters use these terms when a heat wave is predicted in your community:

  • Excessive Heat Watch - Conditions are favorable for an excessive heat event to meet or exceed local Excessive Heat Warning criteria in the next 24-78 hours.
  • Heat Advisory - Heat Index values are forecasting to meet locally defined advisory criteria for 1-2 days (daytime highs = 100-105 degrees Fahrenheit).
  • Excessive Heat Warning - Heat Index values are forecasting to meet or exceed locally defined warning criteria for at least 2-days (daytime highs = 100-105 degrees Fahrenheit).

Preparing for a Heat Wave:

  • Listen to local weather forecasts and stay aware of upcoming temperature changes.
  • Be aware of both the temperature and the heat index.  The heat index is the temperature the body feels when the effects of heat and humidity are combined.
  • Discuss heat safety precautions with members of your household.  Have a plan for wherever you spend time - home, work & school - and prepare for power outages.
  • Check the contents of your Emergency Disaster Kit in case a power outage occurs.
  • Know those in your neighborhood who are elderly, young, sick or overweight.  They are more likely to become victims of excessive heat and may need help.
  • If you do not have air conditioning, choose places you could go to for relief from the heat during the warmest part of the day (schools, libraries, theaters, malls).
  • Be aware that people living in urban areas may be at greater risk from the effects of a prolonged heat wave than people living in rural areas.
  • Get trained in First Aid to learn how to treat heat-related emergencies.
  • Ensure that your animal's needs for water and shade are met.

What to do in a Heat Wave:

  • Listen to a NOAA Weather Radio for critical updates from the National Weather Service (NWS).
  • Never leave children or pets alone in enclosed vehicles.
  • Stay hydrated by drinking plenty of fluids even if you do not feel thirsty.  Avoid drinks with caffeine or alcohol.
  • Eat small meals and eat more often.
  • Avoid extreme temperature changes.
  • Wear loose-fitting, lightweight, light-colored clothing.  Avoid dark colors because they absorb the sun's rays.
  • Slow down, stay indoors and avoid strenuous exercise during the hottest part of the day.
  • Postpone outdoor games and activities.
  • Use a buddy system when working in excessive heat.
  • Take frequent breaks if you must work outdoors.
  • Check on family, friends and neighbors who do not have air conditioning, who spend much of their time alone or who are more likely to be affected by the heat.
  • Check on your animals frequently to ensure they are not suffering from the heat.