Why is there such a thing as a “feels like” temperature? For example, in NYC, it’s 91 degrees today but the weather app says it “fees like” 99 degrees

Question

Why is there such a thing as a “feels like” temperature? For example, in NYC, it’s 91 degrees today but the weather app says it “fees like” 99 degrees

In: Earth Science

Answer 1

It’s because the human body cools itself off via sweating, which can be much less effective in high humidity. Our sweat needs to evaporate off our skin to cool our body, but if there is a ton of water already in the air the sweat doesn’t evaporate as readily and we can overheat easier.

So scientists did a bunch of studying and modeling on the human body, how sweating works, etc, and came up with a general model for how humidity effects the “average person”, it’s not super futuristic science and needs to be taken with a grain of salt but we basically have a scale that says from humidity 20-40%, add 5 degrees F to the thermometer temperature, for 40-60% at 10 degrees, etc.

So if in NYC the thermometer reads 91, and the humidity is 50%, the scale says add 8 degrees for a “feels like” temperature.