A third grand prix on the trot looks set to be disrupted by rain.

Bad weather affected the consecutive Japanese and Korean events recently, and rain is already disturbing the teams as they set up early this week at the Interlagos circuit in Brazil.

F1′s first sign of rain came at the weekend, when a golf tournament contested by Rubens Barrichello in Sao Carlos – a city of the Sao Paulo state – was cut short due to heavy rain.

And as the big teams including Ferrari set up at Interlagos on Monday, workers took cover inside the pit garages when a rain storm struck.

For the weekend, the initial forecasts predict possible showers across Friday and Saturday, with a reduced chance of rain for Sunday.

Last year’s Brazilian grand prix, held in mid October, was badly affected by rain, with delays protracting qualifying to an excruciating 160 minutes.

“There’s always a chance of rain,” said local Barrichello this week.

Red Bull still had the F-duct fitted to its RB6 on Saturday morning in Valencia.

According to the BBC, the Milton Keynes based team has confirmed the downforce-stalling device will also remain on the Renault-powered car for qualifying and the race.

Sebastian Vettel topped the final 60 minutes of practice at the sunny street circuit, with his teammate Mark Webber third, split by Renault’s Robert Kubica.

The two Force Indias were fourth and seventh, with the team having ironed out the problems with its F-duct version.

“(It) is working very well now and it makes a real difference,” said German Adrian Sutil.

Ferrari’s Fernando Alonso was fifth, while the McLarens were just ninth and tenth, and Mercedes’ Nico Rosberg 11th.

“There are a lot of quick cars out there,” said Jenson Button.  “The Ferraris look very fast, so do the Red Bulls, Renaults and Mercedes.”

At the beginning of the last free practice session the track after morning rain was still slightly damp in places. During the last 60 minutes of training was before qualifying in the afternoon but then dry with temperatures around 20 degrees.

The best time in 1:16.058 minutes secured Lewis Hamilton in the McLaren-Mercedes. Team mate Jenson Button came with 0.641 seconds gap to sixth place. The closest runner-up was Mark Webber, Red Bull were missing in the 0.282 seconds on Hamilton. Team-mate Sebastian Vettel ended up with 0.524 seconds behind the fourth position.
In third place was Fernando Alonso in Ferrari (+0.437 seconds) ahead of Michael Schumacher in the Mercedes (+0.478). Nico Rosberg was able to drive due to a problem with the clutch only one timed lap and was in the end led to rank 18 (+1.921).

On the sixth was followed by Robert Kubica Renault (+0.595) from Adrian Sutil in the Force India (+0.615). Nico Hulkenberg finished in eleventh place (+1064). Sébastien Buemi 16 Place (+1.575). Timo Glock was taken to rank 21 (+3.478).