F1's Miami Grand Prix schedule in doubt amid thunderstorm threat - ESPN

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 4 p.m. local 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.

Per U.S. law, any open-air event must be stopped if there's lightning within an eight mile radius. 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 cancelled and the F1 Academy and F2 races moved forwards in order to give F1 the possibility of an earlier race start.

Despite rumours 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 repeat 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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