Ahead of today's opening practice session, the air temperature is 29 degrees C, while the track temperature is 28 degrees. It is 18:00 local time and the sun is low in the sky. Following an earlier downfall the track is still damp, indeed, there is standing water on parts of the track, including a couple of corners, consequently the session has been declared wet. Further rain is expected today and for the remainder of the weekend.
At Hispania, Christian Klien is replacing Sakon Yamamoto for the remainder of the weekend, the Japanese youngster having been laid low by food poisoning. Fairuz Fauzy is in Trulli's Lotus this morning while Jerome d'Ambrosio is in di Grassi's Virgin. Also, let's not forget that Nick Heidfeld replaces Pedro de la Rosa at Sauber for the remainder of the season.
A number of teams have brought updates here, most notably Renault, which has a new front wing, as do McLaren and Red Bull, though, in terms of the Milton Keynes outfit, currently only Webber has access to it.
Seven minutes into the session all twenty-four drivers have been out, all of them on intermediates.
Kubica has a rough time of it at the chicane that is Turn 10 - or the Singapore Sling as it is now known.
Twenty minutes into the session, Klien posts the first time of the day (2:18.621). Moments later, Petrov, who is not running the F-duct in this session, posts 2:16.337.
As Petrov improves to 2:09.423, in the Red Bull garage the new front wing is removed from Webber's car and now Vettel has it. However, the Austrian team is eager to point out that it has two of the new wings available, having clearly learned from the problems it encountered earlier in the season.
Schumacher goes second with a 2:09.922 as Petrov ups the ante with a 2:07.277. Buemi is third ahead of Klien (2:11.462).
Schumacher goes quickest with a 2:04.758 as Glock posts 2:05.137 to go second.
Thirty-five minutes into the session, and with apologies to Michael Schumacher, Felipe Massa is the first of the big guns to come out for a second run. As The Brazilian posts 2:06.485 to go fourth, Glock raises the benchmark with a 2:02.180. Barrichello goes third only to be demoted by teammate Hulkenberg (2:05.379).
Nick Heidfeld's first flying lap sees the German go eleventh (of eleven) with a 2:18.898.
Having improved to second (2:02.297), Barrichello complains of rear-locking. Teammate Hulkenberg consolidates third with a 2:02.610.
Currently fourth (2:03.635), Alguersuari looks spectacular as he improves with a 2:00.655 to go quickest. Elsewhere, Heidfeld goes fourth with a 2:02.588.
At half-time, it's: Alguersuari, Glock, Kobayashi, Barrichello, Heidfeld, Hulkenberg, Schumacher, Petrov, Massa and Senna.
As the track improves, Petrov and Kobayashi filly break the two-minute barrier, the Russian going quickest with a 1:59.856.
As Schumacher improves with a 58.504 to go quickest, Kubica heads down the pitlane. Liuzzi goes quickest in S1 finally crossing the line at 59.614 to go third. Kobayashi re-takes the top spot with a 58.025.
Massa goes third (59.134) despite getting worryingly close to the concrete barriers. Elsewhere, teammate Alonso heads down the pitlane.
Glock is the first driver to make the switch from inters to dry, though there are still damp patches at a number of points on the track. Alonso is also on dry tyres. After a couple of exploratory laps, the Spaniard returns to the pits to change his nose.
With 16:35 on the clock, Hamilton leaves the pits. Elsewhere, Glock takes to the escape road having got it wrong under braking. Kobayashi is still quickest (57.260).
Massa (on inters) improves to second (57.760) having gone quickest in the first sector.
Despite getting very close to the wall in the final corner, Button posts 2:02.373 to go tenth. Hamilton, Webber and Vettel all on track, all on dry tyres.
Barrichello - now down in tenth - complains of a "lazy car" which is locking up everywhere.
On the first flying laps, Webber goes twelfth, Hamilton thirteenth and Vettel sixteenth. Button improves to fourth with a 57.872. Alonso and Kubica are now the only drivers who haven't posted a time.
Button goes quickest in S2, finally crossing the line at 56.228 having gone quickest in S3 also. Sutil improves to third (57.403), ahead of Schumacher and Massa.
A 56.646 sees Alguersuari go second, however, moments later Sutil goes quickest with a 56.226.
As the clock ticks down the times begin to tumble, however, the grip continues to catch some drivers out including Webber.
No sooner has Button gone quickest with a 55.333 than Vettel posts 55.137. Webber posts 56.831 to go seventh.
With twenty-three cars on track, traffic is really proving to be a problem here.
At the death, Hamilton, running the new front wing, posts 56.884 to go tenth. Moments later, Schumacher posts 54.708 to take the top spot only to lose it when Webber crosses the line at 54.589.
The session ends with Webber quickest, ahead of Schumacher, Sutil, Vettel, Alguersuari, Button, Liuzzi, Buemi, Kubica and Petrov.
Alonso is eleventh, ahead of Kobayashi, Heidfeld, Rosberg, Kovalainen, Barrichello, Hulkenberg, Hamilton, Massa, Glock, d'Ambrosio, Senna, Klien and Fauzy.
While Webber will be happy to have scored the first goal of the weekend, the track conditions mean that few questions have really been answered.
To check out our Singapore practice gallery, click here