The Role of the Modern America’s Cup Weatherman

Wind and weather dictate every racing sailor’s racecourse calls, but for the today’s America’s Cup weather team, the work starts well before the first race.
Anderson Reggio
American Magic testing manager Anderson Reggio says accurate weather forecasting is critical to foil-wing and sail selection. Will Ricketson/American Magic

In Auckland, New Zealand, the 75-foot foilers will be wedged into small, inshore boundary-constrained racetracks where wind shifts still matter, but given the speed of the boats and the dimensions of the racecourse, it’s about a minute of sailing between ­boundaries. Tack on shifts? Maybe not. Given the cost of maneuvers, it could very well be worth the distance loss of sailing a header for a short period in order to earn a longer board on the other tack. Change is ­ubiquitous in the America’s Cup, and when the boat type changes, so too does the role of the weather team, an important component of every serious Cup syndicate. In the early days of a campaign, the weather team plays a crucial role in boat design. I can still remember my first Cup campaign, when design-team manager Robert Hopkins explained how the team had commissioned a huge weather study of the winds off Fremantle, Australia, and how the winds change during the racing period from October to February. The study helped the designers come up with dozens of candidate designs that were then “virtually” raced against each other in a digital regatta with the same qualification rounds with ­escalating point value, just like the real thing. Employing a ­science called “game theory,” the Stars & Stripes design team then determined which boat of the many candidate designs would survive the lighter, early springtime rounds of the trials, thrive in the heavy air of the later trial rounds, and still have the speed to win the Cup in the moderating sea breezes of the later summer. It all sounded pretty Buck Rogers-esque to me, but clearly they got it right, because we won the Cup in four straight races after surviving the trial’s early rounds and thriving in the heavy air of the later rounds.

The science of historical weather analysis has greatly improved since those days, and today, Cup weather teams’ early historical research continues to provide an important foundation for the design team. Historical data used includes the “re-analysis products” of weather models plus archived observation data. And because the Cup was held in Auckland in 2000 and 2003, there is a lot of high-quality local historical buoy and sensor data to pull from. At this important stage, teams also benefit from the experience of their weather gurus.

Roger Badham, whose local knowledge of Auckland weather started out in the early days of the 18-Foot Skiffs, has been working with Team New Zealand since the Cup was last in Auckland. American Magic’s Chris Bedford is on his 10th Cup campaign (we were rookies together on Dennis Conner’s Stars & Stripes team in Australia). Whether it’s historical analysis or interpreting today’s weather in Auckland, experience counts, and these veterans add incredible value to the raw science and data they are working with. Logistics is another early-stage subject that Cup weather teams are asked to contribute to. American Magic’s choice of training grounds in Pensacola, Florida, for example, was due in large part to its similarity to the AC racecourses in Auckland. But helping pick the training bases isn’t the end of the weather team’s role in logistics and operations. Juan Vila, a veteran Cup sailor, Volvo Ocean Race-winning navigator and meteorologist for INEOS Team UK, says that at some point in the campaign, pretty much everyone on the team will come to him for his input. And that includes crane operators tasked with safely launching and hauling these flying machines. On a daily and weekly basis, the meteorologist’s input helps the team plan everything, from when and where to sail on a particular day to achieve a particular goal (e.g., light-air transition to foiling) to when to schedule those crucial workdays for the boatbuilding team. Every Cup weather team will utilize a variety of weather models, some of which will be familiar to any sailor and others who are customized for the race area. To keep the “arms race” at bay, Cup rules limit data collection, so no lidar and other “science projects” that have been used in past Cups.


“Valencia (2007) was the height of craziness in ‘weather world,’” Bedford says. “The cold war of weather ­information had gotten out of hand. We’d gone from a Cup campaign with one weather boat to a dozen weather boats, several dozen weather buoys, drones —extremely expensive.”

For this Cup, a communally funded weather-buoy network, managed by PredictWind, has been created, and all teams have access to this live and historical data, as well as instrument data coming off their sailboat and chase boats (allowed only when the team’s sailboat is on the water). Once the race committee gets into action, their wind data (including wind direction and speed on the race marks) will be added to the communal network. Bedford is a fan of the communal concept, as is Badham, who once managed a seven-­person weather team for Emirates Team New Zealand.

“The ‘met’ role changed hugely with the change from slow boat to fast boat” after Valencia 2007. Bedford continues, “With the slow boat, you were a ­critical decision-maker—what side to protect, how to start, how to play the first half of the beat—that was the weather game.” Now, he says, with the speeds of the AC75, there’s a different emphasis, and the role of the met team has become incrementally less when it comes to real-time racecourse management. Once the racing gets closer, however, the weather team will be intimately involved in foil configuration and setup decisions.

Racecourses A through E
The racecourse options for America’s Cup racing in Auckland provide a variety of conditions and viewing options for locals. The goal, organizers say, is to keep the racing visible from land, but is dictated by conditions. Courtesy ACEA

American Magic’s testing manager, Anderson Reggio, says, “The rules require us to commit to our boat configuration a few days before the start of each round,” which is three days before the round robins and five days for Prada Cup Finals and the Cup. “With rounds varying in length from seven to 15 days, the uncertainties of a long-range weather forecast make it hard to get too fancy with your choice of foils.”

But there are other mode changes that can be legally made, and like the Cup days before wingsails, sail-selection decisions are back in the mix. “The rule allows you to carry a Code Zero and a headsail, but with 25-minute races, sail changes just aren’t happening. So it will come down to picking the headsail and the mainsail,” Reggio says. “Sail-limitation rules limit teams to a quiver of 10 mains and 29 headsails (including Code Zeros) to choose from for any race.” Clearly there will be other wind-speed-related mode changes and boat tweaks that teams will be striving to learn about throughout the final work-up to the Trials and the during the racing.

“Setting up the boat for race day is important, but with the new configuration rules, my role in this has changed even since Bermuda,” Badham notes. “There I had a huge role; we had a mode change for every knot and a half of wind speed—­different rudders, elevators and such. I would give a preliminary forecast at 0530, and by 0700, the tips were bogged onto the foil, and they were headed to the autoclave. That’s been ­curtailed this time.”


Bedford says that the dynamic of the racing is different with the short courses and constricted dimensions, which doesn’t allow for much separation between the boats. “The classic ‘left or right’ call is no longer that important, but there is a necessity for the race team to understand the wind field, and I’m on hand to update and interpret what’s happening in real time with the passing of a cloud, or whether the west-coast sea breeze makes it through to the racetrack,” Bedford says. Understanding the wind field during the race remains ultra-important to the sailors. Along with the basic general rules of sailing in pressure and maximizing progress up and down the ladder rungs, we’ve already discussed the importance of understanding shifts and how the skew of the racetrack could affect the tactics of sailors trying to minimize maneuvers. Another wind-related consideration is prestart patterns. For this Cup, we are back to upwind starts, and these foiling boats present new challenges, especially given the geographic constraints of the starting box.

Teams may have certain prestart patterns based on the wind speed, so that might be the final of many important calls the weather team provides before communications are cut off before racing.

Teams may have certain favored prestart patterns based on the wind speed, so that might be the final of many important calls that the weather team provides before communications are cut off before racing. There are five potential course areas the race committee may choose for the America’s Cup Match and Prada Cup challenger elimination series, all of which will be influenced by land effects. The infamous west-coast southwest sea breeze will have a much better chance of displacing the east-coast northeasterly sea breeze by race times later in the day. This double sea-breeze situation is thanks to geographic features—especially the fact that New Zealand’s North Island is very narrow at Auckland’s latitude. Along with predicting which sea breeze will win, geographic effects on the wind flow and strong tidal currents are key features that the weather team is charged with deciphering on the 2021 Cup racetrack. As Reggio points out, most, if not all, of the raceboats will have no speed sensor other than a high-accuracy GPS. To solve the wind triangle and derive true-wind speed and direction on the boat’s instruments, one must add in values for current set and drift. Reggio oversees American Magic’s proprietary current model based on public data, which is loaded into the raceboat’s instrument system to resolve the wind triangle. This method was first employed by Cup teams in 2013 in the racing on current-infested San Francisco Bay. Another “opposites day” type twist to Cup racing in boats that can VMG faster than the wind is that adverse current on ­downwind legs is advantageous!

Though the America’s Cup game keeps changing, one thing that has not is that a ­sailor’s world revolves around the wind, and a Cup weather team remains a crucial element to success. The job begins early each day, with study of the local weather’s big picture—what Bedford calls the “forecast funnel”—before focusing down to the local scale and the bevy of weather models, observations, radar and satellite imagery that all help provide the “guidance” that gets turned into the morning forecast. Communication continues throughout the day with the various briefings, in some form or another, to help the different departments plan. The fun part comes when all the observations have come in, all the model runs have been crunched, and the meteorologists can look up at the sky to try to add even more value to the continuous and dynamic job of forecasting the weather.


“I was probably the first meteorologist on a chase boat doing the weather (in 1983), but with these fast boats, I prefer to be on a good spot overlooking the course,” Badham says. “Before the race, I’ll ride my bike there with my two laptops and a mobile phone. There are days you look at the laptop more than the sky and vice versa, but if you really understand weather, you look at both. No question the weather-team game has changed over my career. I’ve gone from being the one person on the weather team to the arms race that peaked in Valencia, and now I’m back to being a one-man team in what well might be my last Cup.” To put a Cup weather team’s “reduced role” in perspective, consider that during a 30-minute Zoom call with Badham to research this story, he got two calls from Emirates Team New Zealand veteran sailor and coach Ray Davies, who was out on the water with the team’s new AC boat, conferring about passing rain cells and their effect on the wind. And Badham wasn’t even on-site yet. He was still holed up in his quarantine accommodations. Suffice it to say, he expects exponentially more calls as ­racing approaches. Everyone needs their weatherman.