Is the Heat Index Real?

MarianVejcik/iStock via Getty Images
MarianVejcik/iStock via Getty Images

Complaining about the humidity is a mainstay of small talk. “It’s not the heat that gets you, it’s the humidity” is a common refrain around the South, just as “it’s a dry heat” is a go-to line in the desert Southwest. The clichés aren’t wrong on this one—a hot and humid day can have a dramatic effect on both your comfort and your health. We can measure this very real impact on your body using the heat index. 

The heat index is the temperature it feels like to your body when you factor in both the actual air temperature and the amount of moisture in the air. If the heat index is 103°F, that means that the combination of heat and humidity has a similar physical impact on your body as it would if the actual air temperature were 103°F. Even though it’s tempting to think of the heat index as an exaggerated temperature that only exists to make the heat sound worse than it really is, scientists came up with the measurements after decades of medical and meteorological research devoted to studying the impact of heat and humidity on the human body. It’s the real deal.

The dew point is an important component of the heat index. The dew point is the temperature at which the air would reach 100 percent relative humidity, or become fully saturated with moisture like on a foggy morning. Since cooler air can’t hold as much moisture as warmer air, lower dew points reflect lower moisture levels and higher dew points indicate higher moisture levels. Dew points below 60°F are comfortable, while readings reaching 70°F and even 80°F range from muggy to downright oppressive.

Measuring humidity on a hot day is important because moisture is how your body naturally cools itself off. Your sweat cools the surface of your skin through a process known as evaporative cooling. If the air is packed with moisture, it takes longer for your sweat to evaporate than it would in more normal conditions, preventing you from cooling off efficiently. The inability to lower your body temperature when it’s hot can quickly lead to medical emergencies like heat exhaustion or heat stroke, which is why the heat index is such an important measurement to pay attention to during the summer months.

The heat index is generally considered “dangerous” once the value climbs above 105°F, and your risk of falling ill increases the higher the heat index climbs.

Dry climates can have the opposite effect on your body, with the distinct lack of moisture in the air making it feel cooler to your body than it really is. Summers get oppressively hot in places like Arizona and Iraq, but the heat doesn’t affect residents as severely because the air is extremely dry. Dew points in desert regions can hover at or below 32°F even when the air temperature is well above 100°F, which is about as dry as it can get in the natural world.  

In 2016, a city in Kuwait measured the all-time highest confirmed temperature ever recorded in the eastern hemisphere, where temperatures climbed to a sweltering 129°F during the day on July 21, 2016. The dew point there at the same time was nearly 100 degrees cooler, leading to a heat index of just 110°F, much lower than the actual air temperature. That’s not necessarily a good thing. Extreme heat combined with extreme aridity can make your sweat evaporate too efficiently, quickly dehydrating you and potentially leading to medical emergencies similar to those you would experience in a much more humid region of the world. 

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This story has been updated for 2019.

This $49 Video Game Design Course Will Teach You Everything From Coding to Digital Art Skills

EvgeniyShkolenko/iStock via Getty Images
EvgeniyShkolenko/iStock via Getty Images

If you spend the bulk of your free time playing video games and want to elevate your hobby into a career, you can take advantage of the School of Game Design’s lifetime membership, which is currently on sale for just $49. You can jump into your education as a beginner, or at any other skill level, to learn what you need to know about game development, design, coding, and artistry skills.

Gaming is a competitive industry, and understanding just programming or just artistry isn’t enough to land a job. The School of Game Design’s lifetime membership is set up to educate you in both fields so your resume and work can stand out.

The lifetime membership that’s currently discounted is intended to allow you to learn at your own pace so you don’t burn out, which would be pretty difficult to do because the lessons have you building advanced games in just your first few hours of learning. The remote classes will train you with step-by-step, hands-on projects that more than 50,000 other students around the world can vouch for.

Once you’ve nailed the basics, the lifetime membership provides unlimited access to thousands of dollars' worth of royalty-free game art and textures to use in your 2D or 3D designs. Support from instructors and professionals with over 16 years of game industry experience will guide you from start to finish, where you’ll be equipped to land a job doing something you truly love.

Earn money doing what you love with an education from the School of Game Design’s lifetime membership, currently discounted at $49.

 

School of Game Design: Lifetime Membership - $49

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Snow Kidding: A Polar Vortex Could Hit the Eastern U.S. This Month

You may not want to put your ice scraper away just yet.
You may not want to put your ice scraper away just yet.
Tamara Dragovic/iStock via Getty Images

If you’re in the eastern U.S. and planning some gardening sessions, you might want to double-check the forecast. According to the Washington Post, a polar vortex like the one that hit the U.S. in 2019 is lurking and prepared to unleash chilly air in the eastern half of the country. Some areas can even expect snow—in Pennsylvania, maybe as much as an inch.

Powder is expected in the Northeast and Mid-Atlantic areas, with cool temperatures spreading from the Upper Midwest to New England, which might see a topcoat of snow beginning this weekend. Georgia might get some frost. The cold front could experience 20-degree reductions in temperatures, with Minneapolis dropping into the upper 40s and Chicago seeing 45°F.

Areas like Providence, Rhode Island; Hartford, Connecticut; and Boston—normally in the 60s this time of year—might not climb out of the 40s over the weekend. New York City, which has been enjoying temperatures in the 70s, won’t get out of the 50s.

Blame the peculiar weather on the polar vortex, which may be best described as an arctic hurricane that transports freezing air south when warm weather pushes it out of northern Canada, Alaska, or Greenland. In other words: There’s no rush on installing that air conditioner just yet.

[h/t Washington Post]