Extreme Heat and Health

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Extreme Heat and Health


Key Takeaways

  • Extreme heat is the leading cause of weather-related deaths in the United States.
  • In the future, Harris County is expected to have higher temperatures and more extreme heat days.
  • High temperatures and humidity can cause heat-related illnesses, such as heat cramps, heat exhaustion and heat stroke.
  • Certain populations, such as the elderly, young children, and those with diabetes, are at  increased risk of heat-related illnesses.
  • Reducing exposure to high outdoor temperatures and having access to air conditioning can provide relief and prevent heat-related illnesses.
  • There are ways to reduce urban heat through better urban design, the addition of trees and greenspace, and the reduction of greenhouse gas emissions.


Extreme Heat in Harris County

Hot and humid weather is typical within Harris County and Southeast Texas. According to the Climate Impact Assessment for the City of Houston, more extreme heat days, hotter nights, longer summers and higher energy demands are projected for the Greater Houston Area in the future.

When temperatures become extremely high and humidity levels peak, heat stroke, heat exhaustion, heat cramps and dehydration become a concern. Extreme heat can also exacerbate pre-existing conditions such as cardiovascular disease, asthma, chronic obstructive pulmonary disease (COPD), and diabetes.

Heat Stroke
Heat stroke occurs when the body temperature rises quickly, sweating does not occur, and the body is unable to cool down on its own . Body temperature may rise to 106°F or higher within 10-15 minutes. 

Warning Signs
  • Very high temperature (>103º) 
  • Nausea 
  • Red, hot, dry skin
  • Confusion 
  • Fast, strong pulse
  • Unconsciousness
  • Dizziness 
  • Throbbing headache

What To Do
  • Move person into the shade or an air-conditioned room
  • Bring the person’s temperature down using any method available - ice packs, cool water in a tub or shower; cool water from a garden hose; or wrap the person in cool, wet sheets 
  • Do not give person any fluids to drink 
  • Perform CPR if needed

Heat Exhaustion
Heat exhaustion can develop after several days of exposure to high temperatures and not enough or unbalanced replacement of fluids . People at greater risk include the elderly, people with high blood pressure, and people working or exercising in a hot environment. 

Warning Signs
  • Heavy sweating
  • Nausea or vomiting 
  • Muscle cramps 
  • Fainting 
  • Weakness 
  • Cool and moist skin 
  • Dizziness 
  • Fast and weak pulse 
  • Headache 
  • Fast and shallow breathing

What To Do
  • Find an air-conditioned environment and rest 
  • Take a cool shower or bath 
  • Drink cool, nonalcoholic beverages

Heat Cramps
Heat cramps are muscle pains or spasms - usually in the arms, legs, or abdomen. Sweating depletes the body’s salt and moisture. If you have heart disease or are on a low-sodium diet, get medical attention for heat cramps. 


What To Do 
  • Stop all activity and sit quietly in a cool place 
  • Drink water, clear juice or a sports beverage 
  • Seek medical attention for heat cramps if they do not subside in 1 hour


Who Is Impacted?


Who is Impacted_4.5.2021



Extreme Heat Vulnerability

Extreme heat can impact people and communities differently, so it is important to look at more than just temperature when determining which areas of our community are most vulnerable. The Extreme Heat and Health Vulnerability Assessment measures the degree to which our communities are susceptible to injury, illness, damage, or harm caused by high temperatures and humidity. Find out more about Climate and Health Vulnerability Assessments here.