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.

The One-Day Record Snowfalls In Each State

Greenseas/iStock via Getty Images
Greenseas/iStock via Getty Images

Long after you’ve grown out of believing in magic, every thick, whirling snowstorm still seems to have been cast upon your town by a winter warlock (or Frozen’s resident ice queen, Elsa).

It’s also pretty magical when those inches of stacked snowflakes add up to a message from your manager telling you not to come into the office. In southern states like Georgia or Florida, sometimes all it takes is a light dusting.

But even those characteristically balmy places have hosted some serious snowstorms over the years, and David Cusick for House Method crunched the numbers to find out which ones made the record books. Using data from the National Centers for Environmental Information, Cusick created a map showing the one-day record snowfall for each state.

Florida finished in last place with a scant total of 4 inches, which occurred in Santa Rosa County on March 6, 1954. About two years before that, on January 14, 1952, Colorado had a staggering 76 inches—that’s more than 3 inches per hour—a national record that’s remained unchallenged for nearly 70 years.

Made with Flourish

But other states have come close. The snowstorm that hit Colorado in 1952 wreaked almost as much havoc in California, whose record from the same day was 75 inches. And Washington saw 70 inches of snow in November 1955, beating its 52-inch record from 1935 by a full 18 inches.

Though Midwestern states have gained a reputation for harsh, snowy winters, their one-day record snowfalls are surprisingly moderate. The Illinois and Indiana records are 24 and 26 inches, respectively, both slightly lower than Ohio’s 30-inch snow day from 1901. In 1993, North Carolina bested Ohio’s record by 6 inches.

Wondering how your individual county’s record compares to the overall state one? Cusick created a map for that, too, which you can explore below.

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[h/t House Method]

Gorgeous Timelapse Shows What a Year in Vermont Looks Like in Two Minutes

Kirkikis/iStock via Getty Images
Kirkikis/iStock via Getty Images

If you live in a state with a middling climate where seasonal changes are mostly just the difference between warm and cool breezes, you might not fully understand the impulse to take a photo of your front yard every single week for an entire year.

If you live in New England, on the other hand, you can probably identify with Jennifer Hannux, a Vermont resident who did just that. Then, she edited the 52 photos into one glorious, two-minute-long timelapse and posted it on Twitter.

Hannux, whose Twitter handle is @VermontJen, took the photos from her front porch, which overlooks a sometimes-grassy, sometimes-snowy clearing that leads into an expansive forest with Mount Ascutney visible beyond it.

The video features lush summer greenery, ethereal snowscapes, vibrant fall foliage, and just about every sunrise color you can imagine. Overall, it’s a breathtaking homage to Vermont’s natural beauty, and a pretty compelling reason to consider relocating to New England’s least-populated state. It’s good timing for that, too, since Vermont’s government just launched a program that could pay you up to $7500 for becoming a full-time resident and employee in the Green Mountain State.

This is far from Hannux’s first foray into landscape photography—according to NECN, she posted a similar (albeit snowier) timelapse of images taken from her front porch in 2018. She also runs a photography business called Northeast Kingdom Photography, which you can check out here.

[h/t NECN]

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