For home run hitters, winds are major players, and a study’s findings about Citizens Bank Park may surprise you

When the Phillies host the Colorado Rockies on Thursday afternoon at Citizens Bank Park, the forecasts are calling for winds gusting to 30 mph blowing straight out to right field.

But where they play the game — two stories below the street in a neighborhood whose elevation is only about 10 feet above sea level — chances are excellent that the breezes will be swirling, according to an analysis commissioned by Major League Baseball.

In any event, the winds won’t necessarily help Kyle Schwarber or Bryce Harper: Among the 30 parks, MLB ranked the Bank at No. 3 for winds that kept balls from flying out of the park in the 2023 and 2024 seasons.

A computer-modeled and statistical analysis estimated that winds at the Bank cost Harper several homers. (Under the axiom that life is unfair but sometimes works to one’s advantage, he apparently made up for it elsewhere.)

“I could believe that the ballpark could be oriented to make life pretty hard for players on some days,” said D.J. Pisano, a physicist who includes the Bank among the 34 baseball parks he has visited.

A Major League Baseball game is a spectacle that in most venues takes place in the nonlinear chaotic playground known as the atmosphere. A stadium adds more layers of chaos.

As a player in the outcomes, the winds may trump the “torpedo bat.”

The wind analysis was the product of sensors installed in all 30 parks and computer modeling by Weather Applied Metrics, said Clay Nunnally, an MLB scientist.

Among the counterintuitive findings at Citizens Bank Park: Winds blowing from the third-base side, as forecasters say they will be Thursday, actually can shorten the flights of balls hit to right, and “give a little boost” to balls hit to left.

Nunnally said the winds that are starching the flags in dead center matter if a ball is hit 100 feet or higher.

But winds behave differently when they encounter hard barriers, as they are apt to do inside a stadium, where they can behave like so many pinballs.

As breezes pass the 235-foot-high scoreboard on the center-field side, winds blowing in from left can impair the flight of balls hit to straightaway center, the analysis found.

Said Pisano, a former professor at West Virginia University now with the University of Cape Town: “If you have a strong west wind, I imagine you could get some serious swirling effects there.”

MLB was chary with sharing the wind study’s player- and ballpark-specific data. But Phillies.com writer Todd Zolecki reported that the analysis showed Harper losing a total of six homers to the Bank’s winds in the 2023 and 2024 seasons.

But another analysis suggested he had better luck elsewhere.

In a separate study, the MLB stat gurus took a shot at estimating how much help the environmental factors of ballparks had to offer for the home-run quests.

Using elevation, average temperatures, and other typical conditions in the stadiums in which the homers were hit, it attempted to calculate how many round-trippers a batter would have slugged, given exit velocities and launch angles.

Favorable conditions resulted in Harper’s hitting seven more homers in the 2023 and 2024 seasons than he would have hit in the typical environments at those ballparks.

In MLB’s “park factor” ratings, the Bank was in the top five for being homer-friendly. Among other favorable factors was its high average temperatures during the baseball season.

University of Illinois physicist Alan Nathan has calculated that every increase of three degrees can add a foot to the flight of a ball.

Humidity has a lesser impact, Pisano said, but it can be all the difference between a ball hitting a wall and going over the fence, as higher dew points aid flight. Being near two rivers, Delaware Bay, and the Atlantic Ocean, Philly can get plenty steamy.

Pisano cautioned against taking the computers too literally. (Meteorologists would be the first to agree.)

“They are only as good as the effects that are put into their simulations and only valid if the real conditions match the simulated ones closely,” Pisano said.

It all depends very much on who is pitching that day.