Lightning threat looms over Miami as F1 returns with upgraded cars and new rules

• Season resumes in Florida after five-week break

• Ferrari and McLaren aim to close gap on Mercedes

With Formula One returning after its early season enforced break, the Miami Grand Prix is proving an enticing prospect given most of teams used the time to work furiously on upgrades to their cars. Many of which are being deployed here. Intriguing enough were it not also for the updated regulations being given their debut outing and the threat of lightning storms on Sunday potentially causing a schedule change.

Five weeks have passed since the last round in Japan on 29 March after the Saudi Arabian and Bahrain GPs were cancelled because of the war in the Middle East, a break welcomed by many as an unexpected opportunity to assess their cars which are still very much a work in progress after the rule changes this season.