Here’s a cute little explanation of how humidity effects us, care of WCCO:

According Park Nicollet Dr. Mark Seaburg, our sweat doesn’t evaporate well when it’s so humid outside.

“It comes out of our pores, but it doesn’t go into the air,” he said. “The cooling effect of perspiration happens when it goes into the air.”

Therefore, our bodies try to cool themselves by bringing blood closer to the skin. That takes the blood away from our muscles and brain which makes us feel sluggish.

Humidity also does a number on a person’s hair. The water in the air is absorbed by our hair. That water breaks down the hydrogen molecules in our hair. For some people, the water weighs the hair down and flattens it. For others, it expands it and makes it frizzy.

It helps to stay inside because air conditioning works by bringing humidity down. Doctors recommend drinking water and taking breaks from working out when it’s so humid outside.