Heat Waves

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Overview

The National Weather Service developed the heat index to help people identify days when the risk for a heat illness is higher than normal. During a heat wave, the heat index is excessive for many days in a row. Everyone has an increased risk for a heat-related illness during a heat wave.

A heat-related illness can be more serious for:

  • Older adults, who may not notice excessive heat, do not sweat as effectively, or do not feel thirsty.
  • Infants and children, who can't transfer heat very well.
  • People with chronic medical conditions, such as heart disease, mental illness, or being overweight..
  • People with developmental problems.

Other things that affect a person's risk for a heat-related illness during a heat wave include:

  • Living in cities, because heat is trapped by tall buildings and air pollutants.
  • Living alone.
  • Working outdoors.
  • Exercising outside.
  • Not having cooling devices, such as fans or air-conditioning.

Related Information

Credits

Current as of: March 2, 2023

Author: Healthwise Staff
Medical Review:
William H. Blahd Jr. MD, FACEP - Emergency Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine

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