Wimbledon's Rain Signalling System

It can be frustrating whenever rain disrupts play during the early to mid-rounds at Wimbledon. However, as observed last weekend, I find beauty and joy in watching the exquisite synchronized ballet of the grounds crews. Court 18 is my favorite to watch during a rain delay because it is visually appealing, gives a sense of how fans are moving around, and shows what the sky looks like. It also has a persistent view of a technical mechanism that I nerd out over.

Last weekend, I launched a contest to see if readers could figure out exactly what particularly appeals to me about Court 18 based on a photo. Unless someone figured it out overnight, there were no correct answers. Assuming that is the case, I will be drawing a winner later today from the people who submitted a legitimate unique guess prior to 5:05 a.m. Central Time, which is the daily scheduled publication time for this site.

The correct answer is highlighted in the photo below. I am guessing that most people still won’t know what it is.

Every Wimbledon court has a display of a discreet signalling system that coordinates the tarp crews actions in the event of rain. It is a simple number ranging from 1 to 8 that coordinates the tarp crews on each court. Optimizing the deployment and removal of the court covers is critical for optimizing play. The system was developed and is managed by Wimbledon’s meterology department, which of course they have.

According to a New York Times article published last year, this is what each number signifies:

1: Possible showers
2: Chair umpire discretion to halt the match
3: Increasing likelihood of rain
4: Immediate action is required to cover the courts
5: Inflate the tarps
6: Deflate the tarps
7: Uncover and roll up the tarps
8: Prepare the courts for play

When the number is “1,” it alerts the tarp crews to be ready to spring into action. When the number goes to “2” or “3,” the umpire can halt the match either because precipitation has made the court surface slick or because rain appears imminent and the match is at a good stopping point.

When the signal goes to “4,” umpire discretion has ended. The grounds crew springs into action and pulls the umpires’ stand off the court with the umpire still in it. If the rain is expected to be light, the tarps are not inflated, but when heavy rain occurs or is anticipated, the signal of a “5” prompts the crew to secure the edges of the tarp and to activate the inflation system.

The remaining numbers signal preparations for the resumption of play. “6” signifies that the tarps should be deflated in anticipation that the rain is ending. “7” directs the crew to uncover and roll up the tarps, and “8” is to prepare the court for play. On several occasions this year, the tarps were pulled, but the essential court accessories, such as the net, umpire stand, player chairs, etc, were not put into place. “7” provides a pause point should the tarps need to be quickly redeployed.

I love Wimbledon’s rain alert system as it enhances my viewing experience when the tournament is interrupted by rain. It is a meticulous system of efficiency that brings me great joy.