Rain looks set to disrupt the final session of running on Thursday at Jerez.
It began to rain at the southern Spanish venue late on Wednesday, and worsened overnight. Teams were greeted with a sodden track and drizzle on Thursday morning, but many teams opted to persevere by sending cars onto the track.
Teams also ruled out extending the test for another day, as the upcoming test at Barcelona kicks off on Monday and teams need to be fully set up at the venue by Sunday night.
Also emerging from Jerez on Thursday is news that Renault’s Giancarlo Fisichella is not feeling well and has opted to sit out the final day.
Nelson Piquet Jnr was scheduled to replace him.