Ahead of today's second free practice session the air temperature is 24 degrees (C), and the track temperature is 52 degrees. It remains sunny and humid (49%).
The teams that really need to make a step forward this afternoon are Renault and Honda, both of whom were disappointing this morning.
When the pitlane opens, Anthony Davidson is first out, closely followed by Schumacher, Sato, Heidfeld, Sutil, albers, Kovalainen, Fisichella and Wurz. All the teams are using their race drivers in this session, Williams and BMW having used Nakajima and Vettel, respectively, this morning.
This time around there are no installation laps, it's straight down to business. Once the dust has settled, Trulli leads the way, ahead of Webber, Liuzzi and Kovalainen.
Speed tells his crew that his brakes feel strange, "spongey" even, and that he wonders if there's something underneath the pedal. Suggestions on a postcard…
Just seven minutes into the session and there are fifteen or sixteen cars on track. Hamilton goes quickest (37.323), but is way of this morning's pace. Moments later, Alonso takes the top spot with a 37.053.
In the Ferrari garage the mechanics are using a torch to look inside Massa's car. Back on track, teammate Kimi Raikkonen goes third (38.014).
Jenson Button goes fourth, giving Honda, and indeed the Englishman himself, hope that things are improving. Elsewhere, Kubica goes quickest in the first sector. The Pole finally crosses the line at 36.717 to go quickest. His boss, Mario Theissen, watches impassively from the pit wall.
No times yet from Schumacher, Heidfeld, Speed, Massa or Coulthard, the Scot having missed most of this morning's session.
The onboard shots make it very easy to see who is on the soft compound, now that Bridgestone has painted a white line in the second groove. As Raikkonen gets well and truly crossed up, Schumacher goes fourteenth with his 'stripey' soft tyres.
Massa is finally on track, which leaves Coulthard as the only driver that hasn't posted a time. The Brazilian, on his first flying lap, goes seventh with a 37.783.
It's Kubica, Alonso, Hamilton, Kovalainen - who is still complaining of understeer, especially on his early laps - Raikkonen, Fisichella, Massa, Heidfeld, Button and Schumacher.
As Coulthard begins his first flying lap of the afternoon, teammate Webber goes second with a 36.906.
As Massa lock up big-time, two-time World Champion Mika Hakkinen watches proceedings from the McLaren garage.
As Alonso prepares to begin a hot lap, he weaves from side to side generating as much heat into his tyres as possible. Judging by those white stripes he's on the soft compound. Elsewhere, Fisichella goes second (36.827).
Raikkonen takes the top spot (36.669), as Alonso fails to improve. Button is on track, attempting to improve on eleventh, while teammate Barrichello languishes in last place, 4s off the pace and having completed just 5 laps.
Just under an hour remaining; Raikkonen, Kubica, Fisichella, Webber, Kovalainen, Alonso, Hamilton, Massa, Coulthard and Heidfeld.
Barrichello is back on track, as Webber goes quickest in sector two. The Australian loses a load of time in the final sector, and consequently fails to improve, while the Brazilian can only manage twenty-first, crossing the line at 1:40.292.
Massa is on a hot lap, going quickest in the first two sectors. The Ferrari driver crosses the line at 1:35.780, beating the previous best time (Raikkonen) by 0.889s.
Nico Rosberg goes second, splitting the two Ferraris. Meanwhile, his teammate, Alexander Wurz, who didn't take part in this morning's session, is down in seventeenth, over 3s off the pace.
Both Spykers remain at the bottom of the timesheets, along with Barrichello, the new aero package not having the effect the Dutch team had hoped for. The Silverstone-based outfit was the only team not testing here last week.
In his enthusiasm to improve on sixth, Webber goes wide, the Australian appearing to overdrive the car.