Heat Waves and the Heat Index

Have you ever heard the term “heat wave” on the news? Maybe you’ve seen illustrations of something called a “heat index” in the newspaper or online. A heat wave indicates excessive, unseasonably warm temperatures while the heat index helps us to quantify the heat being experienced.

Learn how to read and comprehend the heat index and survive the next heat wave with help from Aire Serv®.

What Is a Heat Wave?

Depending on where you live in the world, a heat wave may be defined in different ways. For our purposes, we rely on The United States National Weather Service definition of a heat wave: a spell of “abnormally and uncomfortably hot and unusually humid weather” spanning two or more days.

Heat waves may be high or low in humidity and contribute to drought, health problems, and even heat-related mortalities. Changing weather patterns due to climate change and the heat-trapping nature of carbon dioxide and methane have made heat waves more common, more unpredictable, and longer in duration.

What Causes Heat Waves?

When a high-pressure system stalls and hovers over a specific region, it can capture warm air beneath it, causing stifling temperatures. There is no way to artificially end a heat wave or to move a pressure system. Heat waves only subside when a stronger pressure system forces the offending high-pressure system out of the way.

Shifting weather patterns, stronger pressure systems, deforestation and increased industrialization are all contributing to the frequency and intensity of excessive heat events.

Heat Waves & Health Problems

Prolonged exposure to extreme heat is dangerous to all individuals but to those who are very young and very old. Outside of problems like sunburn or heat rash, problems arrise when individuals have problems cooling themselves. Heat exhaustion, heat cramps and heat stroke are three dangerous complications of heat exposure.

Learn more about heat-related illnesses from the Centers for Disease Control and Prevention.

What Is the Heat Index?

Heat index compares the temperature on the thermometer to the relative humidity in the air.

In general, the heat index shows that:

  • Low temperature, high humidity = low to medium danger
  • Low temperature, low humidity = low to medium danger
  • High temperature, high humidity = high to extreme danger
  • High temperature, low humidity = high to extreme danger

If you’re curious about the heat index in your area, use the National Weather Service’s Meteorological Conversions and Calculations Heat Index Calculator to calculate the exact heat index you’re experiencing.

Local branches of the National Weather Service are charged with issuing heat watches and warnings for regions throughout the United States.

These heat advisories follow the following scale:

  • Heat Advisory: Issued when the maximum heat index temperature is expected to be 100 degrees or higher for at least two days, and nighttime air temperatures will not drop below 75 degrees.
  • Excessive Heat Outlook: Issued when conditions are right for an excessive heat event to occur over the course of the following week.
  • Excessive Heat Warning: Issued when the daytime heat index temperature is expected to be 105 degrees or higher and not drop below 75 degrees at night. This is the most urgent category of heat watch or warning and may not be ignored.
  • Excessive Heat Watch: Issued when an excessive heat event may take place within the next 24 to 72 hours.

*Temperature ranges may vary based on the region of the country.

How to Survive a Heat Wave

  1. If you can’t take the heat, get out of the kitchen—literally!
    1. Avoid using stoves, ovens, toasters—anything that produces heat inside your home.
    2. Focus on eating light and cool, easy-to-digest meals.
  2. Exercise, work out or play at the coolest time of the day.
  3. Wear cool, loose-fitting clothing.
  4. Drink the recommended amount of cool, decaffeinated, non-alcoholic beverages recommended for your gender and body-type.
  5. Avoid overcompensating for the heat by drinking too much water too quickly (water toxicity) and lowering your blood sodium level.
  6. Reduce time in the sun. Apply and re-apply sunscreen.
  7. Use air conditioning or portable AC units to cool your home.
  8. Spend time in the coolest part of your home: the basement or a room in your house that is shaded by trees or other buildings.
  9. Keep the drapes or blinds closed.
  10. Keep pets and children indoors.
  11. Monitor, pets, friends and family - especially small children, for signs of heat-related illnesses.
  12. If you do not have a means to cool your home during an excessive heat event (you don’t have air conditioning, or you lose power), head to your local mall, library or cooling station.

Breathe Easy With Cooling Services From Aire Serv

Looking to install, repair or replace your go-to cooling system before the next excessive heat event? Don’t wait for the mercury to rise, schedule an appointment online or contact your local Aire Serv to get started. Let us help you breathe easy, knowing you can trust in your home’s cooling systems.

Breathe Easy with Aire Serv

  • Upfront Pricing: We know that you want to know what you’re getting yourself into when you schedule service. We price by the job, not by the hour.
  • Anytime Service: We’re there when it’s convenient for you: 24 hours a day, seven days a week.
  • No Overtime Charge: We have the same low pricing any time of day or night, weekends, or holidays.
  • “Fixed Right” Promise: You want the issue to be fixed—and fixed right. We promise it’ll be fixed right the first time, or it’s free.

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