Ahead of this afternoon's all-important qualifying session the air temperature is 26 degrees C, while the track temperature is 30 degrees.
After this morning's free practice session, which, thanks to the conditions, was something of a lottery, it remains to be seen how this afternoon's session will take shape. It might be sunny right now, but in Monaco's unique micro-climate things can change without warning.
As for how important pole position is here – ignoring the obvious pitfalls that await drivers at Ste Devote on the first lap - there is the ominous fact that for nine of the last twelve years the driver who has started from the front row has gone on to win the race. Therefore, one could argue that anyone not starting from the ‘top spot’ tomorrow might as well give up any hope of taking home some silverware and mixing it with the Grimaldis on the podium.
Fernando Alonso walks up the pitlane towards the McLaren garage, he's followed by Michael Schumacher, who must surely be feeling that little competitive tickle in his tummy. The two greet one another, and the Spaniard's pleasure at meeting his former sparring partner seems genuine. Meanwhile, it's started raining.
It's a brief shower, and by the time the lights go green for the start of the first phase of the session, it has stopped. Indeed the track is already beginning to dry.
Jenson Button is first out, followed by Barrichello, Kubica, Coulthard, Webber, Rosberg and Wurz.
Button posts the first time of the session but it's way off target, the Briton having slowed down to allow another car to pass. Once the first wave of cars have posted times it's Rosberg who is quickest, though he's quickly demoted by Button and then Barrichello.
An 18.373 sees Kubica go quickest, but this is soon eclipsed by Rosberg. However, all eyes are on Kimi Raikkonen who posts a 17.905 to go quickest, ahead of Fisichella.
2006 winner Fernando Alonso goes quickest, but is instantly leapfrogged by his English teammate who posts a 16.924.
The two McLarens are setting a sizzling pace, with Alonso looking very aggressive. For a brief instant Alonso re-takes the top spot, but Hamilton has the last word, topping his teammate by 0.6s.
The Ferrari duo of Raikkonen and Massa go 2-3 splitting the McLarens, only for Alonso to hit back with a 16.470. It is fast and furious out there.
Of the big names, Webber and Trulli are still in the 'danger zone'.
Although he's top of the timesheets, Hamilton is still pushing, going quickest in the first two sectors. The youngster crosses the line at 15.685, that's 0.8s faster than his teammate.
Interestingly, Coulthard goes out on the harder compound, as Trulli goes tenth, thereby relegating Kovalainen to the danger zone.
As Liuzzi goes fifth, Coulthard pushes hard, keen not to be eliminated at the first hurdle. The Scot posts 17.462 to go eighth, ahead of Kubica and Rosberg.
Less than a minute remaining and Kovalainen and Webber are under pressure. The Australian goes fourteenth, so he's still not out of trouble, same goes for Kovalainen, who goes fifteenth.
Coulthard goes quickest in the final sector, to go seventh, as Ralf Schumacher fails to improve on 18.539 and thereby fails to make the cut.
Therefore we lose Albers, who never posted a time, Sato, Schumacher, Sutil, Speed and Davidson, the celebrations of Barcelona now a distant memory.
Quickest was Hamilton, ahead of Alonso, Raikkonen, Liuzzi, Massa, Rosberg, Coulthard, Barrichello, Button and Heidfeld.
The lights go green and after a short while it is Rosberg who gets things underway. The German is followed by the Renaults, the Ferraris and Trulli.
Rosberg begins his flying lap, the Williams driver pushing hard. At the line it's 1:16.100, as Kimi Raikkonen come to a halt at Rascasse, virtually the same point where Michael Schumacher 'stopped' last year. Stranded, he is almost collected by his teammate, whose lap is wrecked. This is disastrous for the Finn. The replay shows that he damaged his front wheel at the exit of the Swimming Pool.
Meanwhile, Rosberg remains quickest, ahead of Massa, Fisichella, Coulthard and Webber. However, Hamilton is on track. Sure enough, the McLaren driver posts 15.479 to go quickest, as Alonso goes quickest in the first sector, the Spaniard determined to prove a point.
At the line the World Champion posts 15.431 to go quickest, as the BMW drivers begin the first flying laps of the phase. The Pole goes third, as his teammate takes fifth, relegating Webber to the danger zone, along with Raikkonen, Wurz, Trulli and Liuzzi.
Next time around Heidfeld improves to fourth, making it a McLaren 1-2 and BMW 3-4. In the Ferrari garage the crew is working franticly on Raikkonen's car, but the clock is ticking. With three minutes remaining, the Maranello crew appears to give up, resigned to the fact that the Finn's session is over.
Kovalainen is on track, the Finn still rooted in the danger zone, along with Webber and Trulli. The Finn is pushing hard, but he is hampered by Coulthard who is on an out lap. They almost touch as Rascasse, the Scot refusing to give way to the Renault driver. Naught, naughty.
Massa goes fifth with a 16.034, as Coulthard goes eighth, ahead of Webber. There are last gasp attempts by Kovalainen and Liuzzi but to no avail.
Therefore we lose Raikkonen, Kovalainen, Trulli, Liuzzi, Wurz and Button. Meanwhile, it is revealed that the stewards are investigating the Coulthard/Kovalainen incident.
Quickest in the second phase was Alonso, ahead of Hamilton, Kubica, Heidfeld, Massa, Fisichella, Rosberg, Coulthard, Webber and Barrichello.
Both Red Bulls are through to the final phase, for the first time this year, though it remains to be seen what punishment, if any, will be meted out to the Scot.
Ahead of the final, and most important phase of the session, Lewis Hamilton heads the traffic jam at the end of the pitlane. Meanwhile, the stewards announce that Coulthard has been penalised by not being allowed to participate in this phase. This means that Jenson Button is given another bite of the qualifying cherry. With Coulthard appearing to have been demoted to sixteenth on the grid, that appears to be a hefty penalty. Then again, with Kovalainen failing to make the cut for the final phase its debatable as to whether the punishment is sufficient. We sure the Finn and his team will have something to say on the matter.
Hamilton posts the benchmark (15.905), but there's over ten minutes remaining. Massa is one of the first to pit, which suggests the Italian team knows something we don't, a rain shower perhaps. That said, a lap later, Hamilton, Alonso and the BMWs pit, as does Barrichello.
Hamilton goes quickest in the first sector, as Alonso matches him to one-thousandth of a second. The Englishman fails to improve as Alonso consolidates second position.
Massa goes third, ahead of Fisichella and Heidfeld as word goes out that there are spot of rain beginning to fall.
With four minutes remaining it looks as though the rain spots were nothing more, just a few spots. Meanwhile, the drivers prepare for the final assault at the coveted pole position.
Fisichella, Heidfeld and Button are all looking set to improve, but none seem about to challenge Hamilton's pace.
As Fisichella goes third, Massa pits, the Ferrari driver determined to out-gun the McLarens. Kubica goes seventh, with just enough time for one more lap.
Hamilton goes quickest in the first sector, with Alonso just a shade off his pace. The Englishman fails to improve, making a mistake as he comes up behind Webber, while Alonso takes the top spot, despite losing time in traffic.
All eyes are on Massa, who, despite going quickest in the final sector, can only manage third, leaving McLaren with a front row lock-out.
Lewis Hamilton will start alongside the Spaniard, ahead of Massa, Fisichella, Rosberg, Webber, Heidfeld, Kubica, Barrichello and Button.
Although the McLarens have set the pace all weekend, apart from this morning, the Ferraris looked capable of giving them a run for their money. However, Kimi Raikkonen's mistake in the second phase means that barring a major upset the British team should further consolidate its World Championship lead tomorrow.
A great performance from Fisichella and also Rosberg, while Webber gave another of his towering qualifying performances.
Looking ahead to tomorrow, other than keeping a careful eye on what happens at Ste Devote, it will be important to see what happens weather-wise. The forecasters were right about today's downpour, and they're still predicting rain for tomorrow afternoon.
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