Lightning interrupts Thunder's Big Bash finals clash

But as thunder had been reported within a 10km radius of the stadium, umpires had no choice but to delay the game around 7.50pm as the Sydney crowd booed.

Scattered showers had been forecast in eastern NSW on Wednesday but no rain fell on ENGIE Stadium in the hours before the Stars won the toss and sent the Thunder in.

Warner clipped Tom Curran to Marcus Stoinis at extra cover on the second legal delivery of the evening to consign the Thunder to 1-1.

But No.3 Matthew Gilkes (22no) got the Thunder back on track, surviving an umpire review that showed Curran had failed to control the ball close to the ground attempting to catch him.

Play then resumed roughly 15 minutes later with the match reduced to 19 overs a side and the winner set to meet the Sydney Sixers for a place in the final against the Hobart Hurricanes.