Colin Turkington topped the times again in a sodden second practice at Knockhill, which was affected by a sharp, heavy shower before the green flag and a torrential downpour 25 minutes in.

The heavens opened just before the start of the session before the sun broke through, allowing West Surrey Racing’s Turkington to set his best lap of 56.484 on a drying track.

An off for Lea Wood at Leslie’s caused the red flags to fly early on, and after the session restarted, another downpour with 15 minutes to go put pay to any hopes of improvements.

Also taking advantage of the narrow window of good conditions was Turkington’s team-mate Nick Foster, who was just 0.022 behind in second, with Triple Eight’s Sam Tordoff 0.355 back in third.

Tordoff’s team-mate Jason Plato was fourth, with Honda pair Gordon Shedden and Matt Neal continuing the two-by-two theme in the top six. Rob Austin, Andrew Jordan, Fabrizio Giovanardi and Rob Collard rounded out the top 10.

Wet or dry, the early running would seem to indicate the BMW 125i M-Sport again has a good advantage on the rest of the field.

The conditions caused surprisingly few incidents, although the red flags did come out again with seven minutes to go, when Neal had an off at the chicane in his Honda Civic Tourer.

Only 30 cars took part in the session, as the problem suffered by Speedworks Motorsport’s Tom Ingram in first practice was diagnosed as an engine failure. The team is fitting a new engine to the Toyota Avensis ahead of qualifying.