View Full Version : A baseball question for the meteorologists

07-03-2002, 10:37 AM
The Detroit Tigers and Chicago White Sox tied the Major League Baseball record for most home runs hit in a game (12) on Tuesday. As noted in a story about the game:
It was a muggy, 93-degree night -- the hot-and-humid conditions that are optimum for homers.
Anecdotally, I concur with the baseball writer. It does indeed seem, historically, that the home runs really start to fly when it becomes hot and humid.

But does that make any sense? Shouldn't more moisture in the air impede a baseball's flight?

A search didn't produce any league-wide statistics on home runs per month, unfortunately. Or any discussion on this topic.

07-03-2002, 11:38 AM
The issue is temperature: hot air is thinner.

In many major league cities, hot air is accompanied by humidity.

In some hot dry towns, they stay hot and dry so the stadium home run rate doesn't change.

Take a major city - Philly, NY, Balt, Chitown, Boston, Pitts, etc, etc....where temps change....temps go up and so does humidity...so humidity is dragged into the equation.

So, the REAL factor is hot air...which is less dense AND usually more still. And, it's even hotter in the stadium than outside.

07-03-2002, 11:40 AM
science says.....weather and baseball:


07-03-2002, 11:41 AM
from the link above:

"...Even the humidity can add extra distance. Water vapor being slightly lighter than air, very humid conditions can also add a little something extra to the long ball hit to center field..."

07-03-2002, 11:55 AM


07-03-2002, 12:23 PM
Props to Philster for answering the sh!t out of this question.

07-03-2002, 12:47 PM
Yeah, you da man, Philster.

Water vapor is slightly lighter than air? Who knew? (Uh, don't answer that. "Obviously not me" will suffice. ;))

07-03-2002, 12:55 PM
So what does this say about the Rockies' plan to keep baseballs in a humidifier in order to keep the number of home runs from getting too high?

If the air is thinner because it's humid, shouldn't the balls, kept in the same atmosphere, be heavier with water vapor, thus cancelling out any advantage the (thinner) humid air would have?

Or am I way off-base here, and about to be picked off? (hey, I held the metaphor!)

07-03-2002, 01:16 PM
Humid balls: Well, they would be heavier if they absorb any moisture. Sounds perverted.

So, it would reason that they wouldn't travel as far.

Also, when whacked with a bat, some water would absord energy and dissipate energy (some even flying outta the ball with some energy that would otherwise stay in the ball), causing less energy to stay in the ball and less to drive it "outta here!"

Got that?

07-03-2002, 01:17 PM
Humid balls post was answering "postcards" question about putting Rocky balls in a humidifier.

07-03-2002, 03:54 PM
Postcards, huh? The air is drier in Denver.

07-03-2002, 04:07 PM
Originally posted by chriszarate
Postcards, huh? The air is drier in Denver.


in Denver, the overwhelming difference in the air density because of the altitude far outweighs any lack of humidity. As a matter of fact, stated in one of the links I posted on the science of all this (did you read them? Nooooo)....well it stated that the hitter's dream scenario would be:

Denver on a hot humid day.

Why? Well, start with thin air at high altitude and throw in some lighter than air water vapor (high humidity) and you have a hitters dream.

Have we killed this issue yet?

07-03-2002, 04:13 PM
Is a humidor automatically a humidifier? The former is what the Rockies were using. I thought that just maintained a constant humidity level, I didn't think it necessarily involved adding humidity.

07-03-2002, 04:13 PM
A recap!!!

For clarification: Hot air is thinner....plus humidity with lighter- than-air water vapor = balls going farther.

Another factor would be altitude which = even less resistance.

Dream = hot/humid/hi altitude. (see: Denver)

postcards the poster says something about putting the balls in a humidifier in Denver...to reduce the distance they travel.....
...which seems to make some sense, so see my post after his regarding that.


07-03-2002, 04:14 PM
Have we killed this issue yet?
It could be .... it might be .... it is ...... GONE! OUTTA HERE!


07-03-2002, 04:19 PM
Originally posted by postcards
Chill out, PHILster; I just misunderstood what my boy postcards (who I addressed by name) was saying. I thought he was implying the air in Denver is often humid ("If the air is thinner because it's humid ..."). Obviously, I was wrong. Thanks for jumping me. :rolleyes:

07-03-2002, 04:20 PM

if the humidor keeps the balls a little more moist than the outside, then in some sense it's like a humidifier....and you don't usually put anything in a humidifier inasmuch as you humidify an area with one.

So, it makes sense what you are saying: that balls are placed in a humidor. Maybe the dry air makes the balls a little tough or brittle covered.

In any event, a humidor keeps a constant humidity level, probably high enough to keep things from drying out.....keeping them moist, more or less.

Take it to an extreme: a soggy ball is dead weight. Like a wet tennis ball. Now, a baseball is less exaggerated as an example, but it suffers from being 'wet'. Even mildly damp, it can't be as lively as a dry ball ( or one with ideal good humidity to provide a balance between water content and pliability/playability).

07-03-2002, 04:54 PM
Another consideration is that the pitcher should be able to get a better grip on a "humidified" ball.