Does the weather have an effect on football?

In the Ask the Wizard thread, mkl654321 asked, "What dynamics affect football totals betting as the season goes on, the weather gets worse, and there is more information on teams' recent performance? How easy (or difficult) is it to find errors in the line?"

Good question. I'm one to believe that only the wind plays a major effect in football. I think it is a myth that cold temperatures are correlated to low totals. To prove this, I averaged the total by week number in the NFL for every game from the 1983 to 2009 seasons. If it were true, you would expect to see lower average totals in the latter weeks. The following graph shows the results. As you can see, there is very little correlation. If there is one, the later weeks, with colder temperatures have slightly higher game totals. The solid black line is the least squared regression line.



Any comments?

What about something like rain affecting the over/under? The past Monday Night Football game, for example, had at least one pass in the end zone that probably would have been caught if it weren't for the ball being slicker. I don't know if that would affect the scores that much, and I don't know how a sportsbook would try to quantify that, and it would probably be dependent on if a team is running the ball more than passing... a bunch of different variables to take into account, I guess.

"Weather getting worse" should only pertain to snowy fields of play during snowstorms, where the field can't be constantly plowed and/or if the snow comes down heavily during the game. There's GOT to be a reduction in performance during those games. Simple cold weather doesn't mean anything either way, and most teams practice in the rain anyway.

Bottom line: Good teams find a way to score; bad teams do not.

Quote: JerryLogan

"Weather getting worse" should only pertain to snowy fields of play during snowstorms, where the field can't be constantly plowed and/or if the snow comes down heavily during the game. There's GOT to be a reduction in performance during those games. Simple cold weather doesn't mean anything either way, and most teams practice in the rain anyway.

Bottom line: Good teams find a way to score; bad teams do not.

But is that a casual effect or a result? Are you good if your score, or score if you are good?

Anyways, reminds me of the story of one team's QB and Center taking repeated snaps in the cold showers at the training facility. Or that was what they claimed....

I asked my friend Jason about this. Suffice it to say that he knows a great deal about sports betting, in particular how the weather effects it. Here is is reply.

Quote: Jason

In most cases wind is the predominant aspect of weather that most affects a game but not the only one. In baseball and other outdoor sports shadows can have an equal affect, especially early and late season baseball afternoon games. Rain or snow isn't as big of a factor as most people think in football, as it generally affects both the offense and defense equally. An example would be a defensive back against a wide receiver. The rain and snow would slow them down equally, thus giving neither side an edge. Wind can simply eliminate a passing game in football along with kicking. I have seen games where a passing team has been forced to run the ball almost every play due to a strong crosswind. It doesn't happen often, but on occasion the wind is the ultimate decider of a game.

Question: how does the cold weather late in the season affect teams from warm weather cities and/or domed stadiums?

How about extreme conditions like fog (Phily at Chicago in the Fog Bowl), really cold weather (Dallas at Green bay in the Ice Bowl), or the time the field at Three Rivers stadium froze along the sidelines overnight due to a badly placed tarp? About the last, the Raiders claimed Pittsburgh did it on purpose, as most Raiders' passing plays were to the sidelines.

Would there be a better match between total score and air temperature? I think the domes and the stadiums in the south may be washing out the data. If not air temp, perhaps Avg. PPG for stadiums vs. domes over the course of a season would reveal a trend?

Quote: Ayecarumba

Would there be a better match between total score and air temperature? I think the domes and the stadiums in the south may be washing out the data. If not air temp, perhaps Avg. PPG for stadiums vs. domes over the course of a season would reveal a trend?

I thought about restricting the survey to just the cold weather cities with outdoor stadiums. However, if there were an effect, it should have been seen in the overall average.

Still, that isn't a bad idea. I don't know the domed status of every stadium. Can anybody help on that?

Quote: Wizard

I thought about restricting the survey to just the cold weather cities with outdoor stadiums. However, if there were an effect, it should have been seen in the overall average.

Not necessarily. What if teams got a bit better as the season progressed. Or defensive Injuries hurt more than offensive ones. You'd have one factor causing scores to rise, and another causing them to fall (weather). Despite the overall average increase if you isolated outdoor cold weather stadiums you may see the effect of weather, and the average increase from non-cold stadiums could give you your baseline improvement to factor in, right?

Quote: Wizard

Still, that isn't a bad idea. I don't know the domed status of every stadium. Can anybody help on that?

Let's try:

St. Louis
Indianapolis
Minnesota
Detroit
New Orleans
Dallas (though the roof is retractable)
Atlanta
Arizona (retractable)

I'm sure i missed some retractable roofs, and I stand to be corrected (too lazy to check each stadium). Wikipedia has a list Here

Houston has a retractable roof, and Indy's new stadium is retractable. There's 4 retractable roofs (Dallas, Arizona, Indy, Houston) right now in the NFL.

I think another factor with weather is the field type. Natural surfaces can get 'chewed' up and muddy during the rain, while turf will remain intact. The amount of crown will move away more water.

I think the scoring dropoff during the latter half of the season would have more to do with player attrition and fewer meaningful games (teams being eliminated or wrapping up playoff spots) than the weather. Unless the weather is just miserable, but how often does that happen.

I believe I heard today that 44 different QB's have started games already. That has got to hurt point production.

Quote: Wizard

I thought about restricting the survey to just the cold weather cities with outdoor stadiums. However, if there were an effect, it should have been seen in the overall average.

Still, that isn't a bad idea. I don't know the domed status of every stadium. Can anybody help on that?

Atlanta
New Orleans
Indianapolis
Dallas
Houston
Minnesota
Detroit
Arizona
St. Louis

Here is an interesting article on the topic of domed teams having an advantage: from last year's WSJ

Quote: avargov

I think the scoring dropoff during the latter half of the season would have more to do with player attrition and fewer meaningful games (teams being eliminated or wrapping up playoff spots) than the weather. Unless the weather is just miserable, but how often does that happen.

I believe I heard today that 44 different QB's have started games already. That has got to hurt point production.

There are so many factors that influence scores in football, that it's hard to pin down which is more important. I suppose each factor contributes something, positively or negatively, to game scores. The trick is quantifynig each.

As you say, late in the season injuries ahve accumulated, but players injured early in the season also come back (sometimes). For some teams the game have no more meaning, but for others each game is do or die.

As to nasty weather, that can happen anytime. Some places ahve more rain in winter, but others experience rain more or less constantly (think Central Florida), or during the fall. Snow is rather rare, but it can have a huge effect ont he game (remember the snow-plow Miami at New England game?)

Or take the QB situation. Some teams juggle more QBs than a circus performer. The Steelers lost their top replacement due to injury, and the Bears the other week lost their starter and backup to concussions in the same game (and ten sacks to boot). Pittsburgh, I'm sure, will provide a clear example. They scored meagerly in their first four games, except against the Bucs (and Batch got lucky with two TDs). From next week on, their scoring will go up substantially as Roethlisberger takes control of the offense again. SImply put Dixon lacked experience, Batch lacked accuracy and Leftwich didn't play. Big Ben is a veteran, he can be dead accurate (remember The Catch in Superbowl XLIII to win the game) and now he can play.