Can temperature predict MLB baseball attendance and what weather conditions could bring the biggest crowds in 2021?  The answer depends more on the calendar than you might think, especially in this reopening year when potential ticket sales should gradually approach full capacity in some ballparks!  Some time ago, I looked at attendance averages from the last full season for the Minor League Baseball teams. Now we can look in more detail at some drivers of Major League attendance patterns.

Baseball Attendance Related to Temperature

I recently uncovered a couple studies looking at baseball attendance related to temperature and other weather conditions.  The first, a study of MLB attendance solely in relation to temperature was performed by Jordan Bean, a data analytics professional working in the insurance industry.  This research was motivated by the baseball commissioner’s 2018 comment that a downward attendance trend had been due to weather patterns.  At the time that was almost certainly true because of a remarkably cold and snowy April up north, but Jordan’s research expanded the range of years examined to almost three decades. 

It turns out that finding consistent daily temperature data for the MLB cities before 2010 is very difficult.  In the study, which used attendance data back to 1990, Jordan resorted to using monthly average temperature rather than the daily game by game detail.  Considering the factors that drive attendance, this approach makes sense.  Decisions to attend games are often made well before the day of the game.  Since not all fans are closely following the weather forecast, but do notice the current weather, monthly average temperatures should tie to attendance within that month.  The summer months do have the highest per game averages but that could well be a case of a correlation not caused by warmer temperatures. Taken across all stadiums combined, July has the highest attendance, followed by the two other summer months.  April is the lowest attendance month, but May and September were found to be almost as low. 

Though July has the highest overall attendance, we will soon see that there are many MLB cities for which other months have the highest attendance. (Source = https://jordanbean.medium.com/analyzing-mlb-attendance-and-temperature-6cb2b1af2bd4)

Plotting Attendance Against Other Influencers

A second study that I uncovered provides several charts plotting attendance against other influencers. Many of these show unique patterns for each individual major league stadium.  Several MLB cities show a gradual decline in attendance going from June through the hottest months of July and August. In the coldest weather cities, where May and early June occasionally have some chilly days, the July and August attendance stands up very well compared to June.  In fact in Cleveland’s Progressive Field and Chicago’s Guaranteed Rate Field, these are the highest attendance months.  Farther south over the Nation’s heartland where late summer humidity can be extreme, June is the clear attendance winner.  It makes sense to see an inverse relationship between attendance and temperature in the South with outdoor stadiums in locations such as Texas (until 2020), Atlanta, and even Saint Louis and Cincinnati being oppressively hot in July and August.   Then, too, some teams fall out of contention by the dog days of summer causing fan interest to slacken in the warmest part of the year.  Rainy conditions can result in up to a 20% decline in attendance compared to clear skies.  Finally, it should also not surprise anyone that the day of the week (shown below) may have the strongest effect of all, with Saturday attendance figures being the clear winner.

Saturday attendance shows the highest per game average with Monday through Thursday games often having much lower attendance. (Source = https://rpubs.com/spuzzanghera/609595)