Weather Applied Metrics, Ballpark Village, and going where the wind takes you

Soon we might actually have some data on the wind!

Ground broke on the St. Louis Cardinals Ballpark Village in February of 2013 and by March of 2014 it was open to the public. It was a massive investment, costing around $100 million with an aim to create a space for fans to congregate before and after games and spend more money. The first phase mostly added a large building space to house several restaurants and entertainment spaces as well as rooftop seating. Phase two added on to this in 2017, costing around $260 million and adding luxury high rise apartments, office spaces, a hotel, and retail spaces.

But these additions also did something else. Here is Busch Stadium in May of 2011:

Photo by Dilip Vishwanat/Getty Images

And here is the skyline in April of 2024:

Photo by Joe Robbins/Icon Sportswire via Getty Images

Ballpark Village has completely changed the skyline outside of Busch Stadium. Whether for better or worse aesthetically is a matter of personal opinion, but it always made me wonder:

What sort of effect could this have on the actual game?

Intuitively it seems like it would have to have some sort of impact on flyballs, right? There is a giant building out in left-center field, for Pete’s sake. It would have to have some impact on wind patterns — maybe even neutralize them. And we might have a way to test this soon. Over the past two seasons StatCast has been tracking something called Weather Applied Metrics. It allows the measurement of the wind at various points of the game, which is much more precise than the general wind direction in the area or looking at a the way a flag is blowing. Take a look:

What they found was that external conditions, mainly wind, can affect the distance a ball travels by 50 feet in either direction (100 feet total).

That is certainly enough to be the difference in a flyout and a home run.

So now to connect the dots. If we know that wind patterns can play a significant role in flyball distance, are we able to deduce if something like the big ol’ building in left center field caused any changes in outcomes for the St. Louis Cardinals at Busch Stadium? It is kind of hard to say, but let’s give it a shot anyway. Looking at the Park Factors Leaderboard on Baseball Savant, Busch Stadium has always been a pretty neutral park. The distance metric only goes back to 2016. In 2016 the Cardinals were 11th in the league in variable extra distance. As of 2024 they are up to 6th, meaning balls are being hit further, but the largest factor in that increase appears to be warmer temperatures.

Looking at the Park Factor leaderboard shows Busch Stadium as a neutral stadium for both sides of the plate back in 2012, prior to the building of Ballpark Village. This didn’t change much in 2024, if anything the park was even more neutral at a cool 100 in Park Factor, however the park seemed to become more difficult for left-handed batters, with a Park Factor of 98, than righties, where it became easier to hit according to a 101 Park Factor.

I needed more information though, so I dug a little deeper. I looked at home runs per fly ball for every year since 2002 to see if there was any change that might correlate to wind patterns, which might correlate to the construction of Ballpark Village. Here is what I found:

I do not feel comfortable drawing any conclusions from this, but it is kind of neat, right? Keeping in mind that while the differences in the bars on the graph might look to be a lot, we are talking about a few percentage points, the obvious note is that in the season construction on Ballpark Village began back in 2013, we can see a pretty steep drop in homers per flyballs — enough of a drop that I can understand why this narrative originated. There are a lot of things that could factor into this — player profiles, hitting coaches, temperature outside, pitching trends, etc. There is definitely not enough to prove causation.

All this is to say I am extremely curious in these wind effect findings. According the MLB.com in 2023-2024 Busch Stadium had 16 home runs prevented by wind. This by far not the largest, with several teams ahead of them like the Kansas City Royals at 67 home runs prevented by wind, the Chicago Cubs at 56, Seattle Mariners at 55, and several other teams with over 20. Busch Stadium for the most part seems to be a pretty neutral park still. As we dig into the specifics of these wind patterns, though, I am curious to see what more we might find (I didn’t even get into how wind affects pitching)? Could this be used to further optimize lineups? Can players adjust their approach to go where the wind takes them? Is it 3am and I have been reading about this for hours and am starting to get a little carried away? Probably that.

Happy Sunday!

Relevant links:

Wind effect: These ballparks, players were most impacted by the weather | Mike Petriello | MLB

MLB’s most extreme ballpark isn’t in Colorado | Mike Petriello | MLB

Weather Applied Metrics in Major League Baseball | Clay Nunnally | Medium

Cardinals are Considering Moving the Walls at Busch | J.P. Hill | Viva El Birdos