In hot air that's dry, we sweat, it evaporates, we cool off.
In hot air that's damp, we sweat, it doesn't evaporate as easily, we don't cool off as much or as fast, and that makes the air feel hotter.
That's your heat index, folks: humidity and sweat. Sweat is how we regulate our internal temperature--the air pulling moisture off our skin cools us, which is why a spray bottle and a fan feels so good right now.
Why is the heat index important? So what if it feels hotter, and we stay sweaty?
When the air is so full of moisture that it can't suck the sweat from your pits anymore, that means your body can't cool itself. There you are, sitting and soaking in that summer heat like a pot roast in an oven, and like that pot roast your temperature is going to go up. The humidity makes it easier for you to overheat, and cook in your own stanky juices.
Reporting just the temperature is fine in areas with low humidity, but 88F in the desert is not the same as 88F in the hot and juicy swamp that is the Midwest right now--one is warm and the other is dangerous. Sure, meteorologists could just say that the humidity is an insane 79% today, but the heat index puts it in terms that people can understand: with the current humidity, the 88F heat will feel like 105F, little pot roasts, so cool off and stay safe.
And that's why Rush Limbaugh is a fucking moron and an irresponsible asshole.
In hot air that's damp, we sweat, it doesn't evaporate as easily, we don't cool off as much or as fast, and that makes the air feel hotter.
That's your heat index, folks: humidity and sweat. Sweat is how we regulate our internal temperature--the air pulling moisture off our skin cools us, which is why a spray bottle and a fan feels so good right now.
Why is the heat index important? So what if it feels hotter, and we stay sweaty?
When the air is so full of moisture that it can't suck the sweat from your pits anymore, that means your body can't cool itself. There you are, sitting and soaking in that summer heat like a pot roast in an oven, and like that pot roast your temperature is going to go up. The humidity makes it easier for you to overheat, and cook in your own stanky juices.
Reporting just the temperature is fine in areas with low humidity, but 88F in the desert is not the same as 88F in the hot and juicy swamp that is the Midwest right now--one is warm and the other is dangerous. Sure, meteorologists could just say that the humidity is an insane 79% today, but the heat index puts it in terms that people can understand: with the current humidity, the 88F heat will feel like 105F, little pot roasts, so cool off and stay safe.
And that's why Rush Limbaugh is a fucking moron and an irresponsible asshole.