Historically, baseball is a game associated with time spent outside, and baseball handicappers have long tried to adjust for the weather’s impact on a game, whether it’s rain, wind, or temperature variations.
While many games are played indoors, baseball was played outdoors for most of its history.
Baseball was played on real grass, with dirt and sunny skies overhead, for the 19th and most of the 20th century. The sport is known for outfielders squinting in the sun as a fly ball approaches, glove shielding their eyes, and feet planted firmly in the grass.
Scenes like players kicking dirt around the batter’s box as they adjust to their new home for the next at-bat, pitchers digging into the mound just in front of the pitching rubber, and player’s pounding their fists into their gloves as they prepare for the next batter in the outfield have defined baseball for generations.
And for the most part that’s still true.
Outdoors, Domed, or Retractable Roof?
Youth league, high school, and college baseball are still predominantly played outside. From youngsters to aspiring professional baseball players at the highest level, youth and amateur baseball are played outside the same way they’ve always been, with the wind knocking fly balls down and sunny skies overhead.
Even minor league stadiums, including AAA, AA, High A, Low A, Rookie League, and other leagues, are still outdoors for the most part. Players are still blinded by the sun and rely on their sunglasses, eye black, and gloves to track fly balls coming their way.
The Korean Baseball Organization (KBO) has only one domed stadium, the Gocheok Sky Dome. Opening in 2015, the stadium offers a unique version of baseball in South Korea where players are protected from the elements and weather can’t affect the spin or flight of the baseball.
Five of the 12 stadiums in Japan’s professional league are domed. Located in Tokorozawa, Saitama, the MetLife Dome is unique compared to other domed stadiums. It lacks external walls and only has a roof. The stadium is covered overhead but still permits air to circulate from outside the stadium.
The stadium doesn’t suffer from rainouts, but the wind can still play a role at MetLife. When voting on Seibu Lions games, bettors must be aware of this dome’s unique features.
Lastly, MLB has the most retractable roof or dome stadiums out of any professional league. Eight MLB stadiums have either retractable roofs or a dome, preventing rainouts. However, games in the seven retractable roof stadiums can still be affected by wind, humidity, or other weather factors when the roof is open.
1 – Wind Matters
Wind can play a huge role in the outcome of an MLB game. Wind can knock down fly balls, turning a homer into a fly out, or give a fly ball just enough hang time to turn into a cheap homer down the right-field line.
While wind plays a factor in every game, baseball games are not played on wide-open fields, so the wind doesn’t always affect games the way you’d expect.
Major League fields are surrounded by all sorts of features that can affect the course of the wind. In addition to constants like bleachers, seating, and concourses, every stadium has unique aspects of its architecture that can redirect the wind, creating jet streams.
Former Rangers ballpark, Globe Life Park, is one example. The stadium was famous for its jetstream, which combined with the hot, dry Texas air, turned the ballpark into a launching pad for hitters.
The park was the most hitter-friendly park out of all 30 stadiums twice from 2001 to 2012, according to ESPN. How hitter-friendly a park is can be determined by comparing the average number of runs scored by all teams at one park to another, and the Rangers home park consistently graded as a great place to hit.
The jet stream was formed by Texas wind blowing in from the south into right field, swirling around home plate, and blowing back out towards right-center. The wind gave fly balls an extra boost at Globe Life Park for years, turning the park into a hitter’s paradise.
If you’re looking to make a baseball bet, research the wind conditions of the park you’re betting at. If the wind is coming from the right direction strongly enough, you may be able to make a value bet on the over.
2 – Fly Ball Pitchers’ Success Varies
Examples of fly ball pitchers include Chris Young and Marco Estrada.
Chris Young has had an up and down career to be sure. Drafted by the Pirates in the third round of the 2000 MLB draft, Young found good success once traded to the Rangers. Through the first four years of his career, playing two for the Rangers and two for the Padres, Young recorded a 3.68 ERA.
Unfortunately, his career had a dip. From 2008 to 2014, he was below replacement-level. He also missed the 2013 season entirely.
Luckily, the fly ball pitcher had a late-career resurgence. He pitched to the tune of a 3.06 ERA for the 2015 Kansas City Royals and helped the team win the World Series that year. He’s been a fly ball pitcher throughout his career and the park he pitches in can play a huge role.
Marco Estrada is another fly ball pitcher. Despite having lower than average strikeout numbers, he was able to carve out a good career by inducing fly balls. Estrada carried a 4.29 career ERA through his 283 starts.
Parks like the Ranger’s Globe Life Park, the Red Sox Fenway Park, and the Rockies Coors Field are all dangerous for fly ball pitchers.
If you see a fly ball pitcher starting in Coors Field, beware. Fly balls turn into home runs at a high rate there, and the park’s conditions can spell disaster for fly ball pitchers.
3 – Weather Affects Over/Under Bets More
Compared to moneyline, run line, and some parlay bets, over/under bets can be very dependent on the weather.
Since both teams are both affected by the weather, moneyline or run line bets won’t have their outcome changed by strong winds or humid conditions. The wind will affect both team’s fly balls the same and decrease or increase runs totals, but won’t necessarily give one team an advantage.
But there are exceptions. If Marco Estrada, a fly ball pitcher, is pitching against a ground ball pitcher like Luis Perdomo, and the wind is blowing out, Perdomo can be a great bet to win in a moneyline or run line bet.
Despite this, over/under bets and some prop bets will generally be more affected by weather than moneyline or run line bets will.
Strong winds, dry weather, or hot temperatures can all lead to both teams scoring more runs, giving an over bet a good chance to payout on the right day. If you research the conditions of the field before you bet, you can get an edge on an over/under bet.
Certain prop bets also payout for home runs hit. Again, if the field conditions are right and fly balls are likely to leave the park at a higher rate, prop bets like, “Will Stanton hit a home run by the 5th inning?” can be good value bets.
4 – Humidity and Temperature Changes Ball Paths
Humidity and temperature, like the wind, can both affect the ball’s flight and how the baseball acts in a game. While humidity can change the flight due to the air being thinner or heavier, humidity actually has a stronger effect on the ball itself.
Chase Field, in Arizona, is so dry that the team has to store baseballs in a humidor to level the playing field and prevent too many fly balls from turning into home runs. The humidity level of the local weather can have a big impact on how far fly balls will fly that day.
In 2011, Dr. Alan Nathan, a professor at the University of Illinois at Urbana-Champaign, discovered that for every 15 percentage-point change in humidity, the average home run distance changed by 13.2 feet.
Like the wind, humidity can play a big role in over/under bets. As the weather becomes less humid, fly balls travel further, so consider the under when it’s humid and the over on a drier day.
We hope this information helps you consider a few more factors when you place bets on baseball. How much do you consider the weather when placing baseball bets? Do you have any other useful tips? Let us know in the comments.