MIAMI -- Formula 1 might struggle to complete the full Miami Grand Prix if forecasts of heavy thunderstorms come to pass on Sunday.
F1's Miami race is set to start at 4 p.m. Eastern time, but current forecasts suggest rain and storms for most of the day in the area around the Hard Rock Stadium, which the F1 circuit snakes around.
In Florida, sports events must stop immediately upon hearing thunder and, per FHSAA [Florida High School Athletic Association] and standard safety policies, cannot resume until 30 minutes after the last clap of thunder or lightning strike. This "30-minute rule" restarts for any subsequent lightning, commonly causing delays for outdoor events like the Miami Grand Prix.
IndyCar and NASCAR races have been stopped or delayed for similar reasons in the past.
The governing FIA is expected to issue an update on grand prix timings on Saturday afternoon, giving officials time to assess the forecast before deciding whether to shift around the schedule for the following day.
F1's race has three support events on Sunday -- a Porsche Supercup race, an F1 Academy race and a Formula 2 race. Sources have told ESPN that the Porsche Supercup race could be canceled and the F1 Academy and F2 races moved forwards to give F1 the possibility of an earlier race start.
Despite rumors to the contrary on social media, multiple senior paddock sources have told ESPN there have been no discussions around running the race on Monday.
Should a race be delayed or stopped because of nearby lightning, the restart order would not be able to be issued by the FIA until there had been 30 uninterrupted minutes without a strike in the same area.
The FIA will be mindful of the light -- sunset in Miami is at 7:52 p.m., but a race cannot be held when visibility drops below a certain level.
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On a competitive level, a wet race would also create a first under the new rules. F1's regulations state that the battery boost mode must be disabled in the wet, while the power deployment dictated by software within the cars is also capped at 250 kilowatts. Straightline mode for the movable aerodynamic devices at the front and rear of the car is also revised slightly.
Speaking ahead of the weekend, drivers voiced some concerns about what a race in the rain might look like.
Alpine's Pierre Gasly spoke about his laps in the wet at a shakedown event at Silverstone earlier this year.
"It was 30 degrees tire temperature, wheelspinning in sixth gear," he said.
"After Maggotts, Becketts [corners] -- underwear change every lap! It was the most extreme I've ever done in my life."
Drivers are also unsure whether wet weather would increase concerns over closing speeds between cars.
"Because you don't have that engine cut [of the new cars] because the batteries are ... you're not using as much energy. So you might have less cut in the straights and arrive faster at the end of the straight.
"You can find yourself in tricky situations, especially if drivers are driving with different power unit strategies. You've got very little visibility, so that's the trickiness of these rules and something that we need to get to understand a way out of that.
"Because in the wet we are really passengers. In the rain it's not about being brave or not. It's you stay flat out and you hope that no cars in front of you are slower than you -- and you just assume they are on the same speed as you."