80 degrees and sunny sounds like a picture perfect day, right? Round up some friends to go to the beach, play some soccer, anything to get outside. But crank up the humidity, and suddenly you’re bound to be a sweaty, exhausted mess. What gives?
Why does a humid day feel so hot?
First, we need to look at how the body cools itself off. We sweat to squeeze heat out of our body. Water soaks up tons of heat, so it’s a great system. When we sweat on a regular day, it all dries off eventually. That evaporation takes our body’ extra heat along with it. Feels great! But humid air is already chock-full of water. Your sweat doesn’t really have anywhere to go. Evaporation slows down. All that heat stays stuck to you, so you start cooking.
That’s why weather forecasters use a “heat index” to describe the weather. Dry days really do feel cooler.
So next time it’s humid out, make a dive for that AC before you get fried.