Ahead of today's all-important qualifying session, the air temperature is 23 degrees C, while the track temperature is 27 degrees. It remains fairly overcast but dry and quite windy. There remains speculation that there will be rain during the course of the session, and looking at those nasty clouds we don't doubt it.

McLaren have topped the timesheets in all three practice session, but each time the Ferraris have been very much in the running. BMW has chosen to stick to its usual tactic of focussing on consistency as opposed to lap times, however, a technical problem this morning cost Robert Kubica vital preparation time.

While Alonso and Webber have looked good, Sebastian Vettel has been the real star of the show thus far - at least as far as the 'best of the rest' is concerned.

Rosberg is first out, followed by Bourdais, Sutil and Fisichella. Raikkonen is a surprise 'early riser'.

Rosberg posts the benchmark, crossing the line at 17.522, however, Vettel has already gone quickest inn the first two sectors. He crosses the line at 17.030 to go third.

As in all the previous sessions, we are seeing cars having problems staying on the black stuff.

Raikkonen goes second with a 16.810, the Finn unhappy with the handling of his car this weekend. Webber, leapfrogs the Finn, who then takes the top spot with a 16.352.

As Webber goes quickest (16.058), Massa begins a hot lap. The Brazilian takes the top spot with a 15.885, only to lose out to his Ferrari teammate who improves with a 15.627. Note that this is the Finn's fourth flying lap on the hard compound.

Massa takes the top spot back in the battle of the Ferrari's, the Brazilian raising the benchmark with a 15.255.

All eyes on Hamilton, who gets it wrong at the hairpin, but still manages a 15.218 to go quickest. Kovalainen goes third with a 15.476.

Alonso goes sixth, behind Webber, leaving the BMW drivers as the only drivers yet to post a time.

Whereas the Ferraris improve on successive laps, at least on hards, Hamilton fails to beat his previous best.

Kubica, who suffered a driveshaft failure this morning, goes fifth with a 16.007. Elsewhere, Sutil gets horribly out of shape at the final corner, but somehow keeps it all together.

Heidfeld goes fifth (15.746), ahead of Vettel and Kubica.

Five minutes remaining, and Piquet, Coulthard and Trulli are all in the danger zone.

Just the Ferraris on track as the final assault begins. One by one other drivers head down the pitlane to join them.