Your guide to this weekend’s soggy Formula One race

Lightning cancels second practice session; more rain scheduled for weekend.

Formula One traditionally is supposed to be rainproof, but on Friday at Circuit of the Americas, drivers preparing for the U.S. Grand Prix discovered that certain severe weather conditions can scuttle a practice session.

Lightning became the main concern as storms rolled into southeastern Travis County. The dangerous con- ditions led to the cancellation of Friday’s second practice session after it was delayed nearly an hour. Later in the afternoon, skies cleared enough to allow drivers competing in Porsche

Mobil 1 Supercup and Masters Historic support races to conduct their practice sessions.

Strong thunderstorms are expected again Saturday, so it’s unclear how a packed slate of scheduled activities will unfold at Circuit of the Americas. An hourlong practice session is slated for Saturday morning. Then qualifying is set to begin at 1 p.m. The U.S. Grand Prix will take place Sunday, and the rain might have relented by then.

Team Mercedes driver Nico Rosberg was the fastest around the track Friday morning.

Rosberg’s best lap time was 1 minute, 53.989 seconds. Lewis Hamilton, Rosberg’s teammate, posted the fifth-fastest time at 1:55.693. Hamilton is the defending U.S. Grand Prix champion and the reigning Formula One champ. He’s on track for another drivers championship this year.

“For me, it wasn’t a bad day,” Rosberg said. “I did my homework in the morning session and had a good, quick lap. ... It’s a shame for the spectators. They pay a lot of money and didn’t see a single car this afternoon.”

Two Red Bull drivers were second and third — Daniil Kyvat (1:55.224) and Daniel Ricciardo (1:55.592).

Collectively, the drivers finished only 206 laps during the first practice session. That was about 10 laps per driver.

“I love it when it rains, just not on practice day,” Hamilton said. “I don’t think I’ve ever seen rain like this. It’s kind of cool to watch in many ways, but I feel sorry for all the fans who turned out today.”

Drivers don’t have that many tires available for wet conditions. They have three sets for extreme conditions and four for intermediate conditions. They would like to save those for qualifying and Sunday’s race.

An F1 grand prix rarely is stopped because of weather. Since 1950, only nine races have been redflagged and not restarted because of stormy conditions.

Three meteorologists work for Formula One. They set up shop about 5 miles from the track to study the weather conditions.

The main concern Friday was the safety of the marshals who monitor the track at 34 stations. Competition can continue once lightning clears the area for 15 to 30 minutes. From that point, it takes 40 minutes to return the marshals to their track stations.

‘I love it when it rains, just not on practice day.’

Lewis Hamilton

Formula One driver