Ahead of today's sole free practice session, the air temperature is 17 degrees C, while the track temperature is 16 degrees. Not only is it unseasonably cool it is wet, very wet. Indeed, due to the poor visibility the medical helicopter cannot fly which means the start of the session has been delayed.

How wet? Well, parts of the track appear to have turned into rivers, a couple of corners appear to have turned into lakes and one could probably sail a small boat down the pitlane.

There is unlikely to be much activity this morning. That said, Vettel waits resolutely in his car, which is fitted with slicks. The boy means business.

Five minutes into the session, Sutil is told that although the rain is easing off, another heavy downpour is expected within the next ten minutes.

Fifteen minutes into the session, there is a loud thunderclap as fork lightning rakes the increasingly darkening sky. The rain increases in intensity and it looks ever more likely that the session will be a washout, literally.

With just over twenty minutes remaining, the rain appears to have stopped and it is actually getting a little bit brighter. An engine fires up then another, as Race Control announces that the session will get underway at 12:42. This will mean we should get around 18 minutes of 'action'. Nico Rosberg is warned that there are a number of rivers running across the track at various points.

While drivers will want to get a few laps in they must be mindful of the facts that any offs could result in them failing to make it to qualifying in two hours time.

Fisichella is first out and the crowd greets him with as cheer, Kovalainen, Rosberg, Heidfeld, Hamilton and Vettel are among the ten other drivers that join him.

While Fisichella dives into the pits at the end of his installation lap, Kovalainen, Hamilton and Rosberg carry on around.

Kovalainen crosses the line at 1:31.716, however, moments later Rosberg posts 30.483. Elsewhere, Nakajima and Button leave the pits.

As Rosberg raises the benchmark with a 26.712, Kubica, Sutil, Webber and Liuzzi have yet to make an appearance, while there are still only three names on the timesheets.

Rosberg goes quickest in all three sectors, crossing the line at 24.169. Kovalainen is second, ahead of Nakajima and Alonso, however, with nine minutes remaining the rain begins to fall again.

Grosjean spins at Turn 1, however, the Frenchman is able to continue. Moments later, teammate Alonso goes off, but he too is able to carry on.

Rosberg improves to 23.396 as the replay shows that Alonso aquaplaned on one of the numerous rivers, as does Raikkonen.

With just over five minutes remaining, Grosjean goes off again, the Frenchman a helpless passenger as his Renault slides across the track takes to the air and hits the barriers ripping off its nose. When the car comes to a rest it is stranded in a mini lake. The session is immediately red flagged.

The session ends with no further activity, the Renault crew facing a race against time if Grosjean is to take part in qualifying.

Rosberg tops the timesheets, ahead of Nakajima, Button, Alonso, Sutil, Grosjean, Buemi, Trulli, Heidfeld and Webber.