This is why a humid day feels so hot

Eighty degrees and sunny sounds like a picture perfect day!

You can round up some friends to go to the beach, play some soccer or anything else that gets you outdoors.

But if you crank up the humidity, suddenly you're bound to be a sweaty, exhausted mess.

Why does a humid day feel so much hotter?

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First, we need to look at how the body cools itself off.

Bodies sweat to squeeze the heat out and 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's extra heat along with it and it feels great.

But humid air is already chock-full of water so your sweat doesn't really have anywhere to go.

Evaporation slows down and all that heat stays stuck to you, so you start cooking.

That's why weather forecasters use a "heat index" to describe the weather because dry days really do feel cooler.

Next time it's humid out, make a dive for that AC before you get fried.