Extreme cold can have a marked effect on the two essential components of any NFL game: the players and the football.
While the cold may not stop a player from executing an effective play, it certainly makes their jobs more difficult. Cold external temperatures force the body to send less blood to the extremities in order to maintain a healthy core temperature.
Passing completion drops by about 2% during games played in extreme cold. (Illustration by Skyler Rexrode)
In as little as 15 minutes, a player’s grip strength can be cut in half. Not an ideal situation for a quarterback trying to throw a perfect spiral.
The cold air irritates a player’s respiratory system, making it harder for them to catch their breath, and stiffens the muscles so they can’t stretch as well.
These reduced temperatures also cause the body to burn glucose five times faster than normal, meaning there isn’t as much energy left for powerful plays on the field. Reaction times can drop by 45% in these conditions.
Punts made in extreme cold average 3 yards shorter than normal. (Illustration by Skyler Rexrode)
NFL games average a 1.79% fumble rate. During games played in extreme cold, that rate increases to 2.42%, a 35% increase. (Illustration by Skyler Rexrode)
Not only does the cold affect a player, but it also has some influence on the actual football. In extreme cold the air contracts and becomes more dense.
NFL regulations state that all game balls must have a pressure of 12.5-13.5 pounds per square inch (PSI). When temperatures change by a factor of 10℉, pressure changes by a factor of 1 PSI.
This means that an inflated football can actually lose pressure and become slightly smaller and under-inflated when the weather gets colder. Within an hour, a football’s air pressure can be reduced by 20%.
Cold, under-inflated balls also have a lower coefficient of restitution. In other words, the ball becomes less bouncy and will come off a kicker’s foot slower than normal temperatures. Despite all of these small setbacks, overall scoring remains about the same as games played in fair weather.
The air pressure of a football is reduced by 20% in extreme cold. (Illustration by Skyler Rexrode)
Be sure to check your game day forecast!
Field goal accuracy drops by 1.7% during games played in extreme cold. (Illustration by Skyler Rexrode)