Ahead of today's final practice session the air temperature is 23 degrees C, while the track temperature is 40 degrees. It is bright and sunny with barely a cloud in the sky.
Daniel Ricciardo set the pace in both of Thursday's sessions, confirming the wide held view that the Red Bulls would be strong here.
Ferrari appeared to have the edge over Mercedes and while both insist that the gap can be closed, the German team, in particular, looks likely to struggle.
That said, despite their obvious pace, Red Bull insists that as their rivals switch on their various engine modes today the true order should become clear.
Behind the big three, Renault looked to be best of the rest, with McLaren, Force India and Toro Rosso in the mix.
As ever, the big question is tyres, and the conundrum facing teams today is whether to use the ultra-fast hypersofts which are producing record times but not durable, or opt for the lower but longer lasting ultrasofts or possibly even supersofts.
As the teams anticipate this problem ahead of qualifying expect some interesting simulations late in the session, teams probably putting their drivers on back-to-back strategies.
Other than a loose manhole cover in FP2, there were no significant incidents on Thursday, though a number of drivers had close encounters with the barriers, most notably Verstappen and Sirotkin.
The lights go green and Vandoorne is followed by Leclerc, Alonso, Magnussen and Stroll. A mixture of hypers and supersofts.
Following an installation lap each peels off into the pitlane, as at the other end Raikkonen, Bottas and Hartley head out.
Raikkonen posts the first time of the day (13.729), as Hartley is told to "keep working on the brakes".
Bottas posts the second time of the day (13.852) as Hartley crosses the line at 14.385 and Hamilton 14.379. All are on the hypers.
Vettel posts 13.150 to go quickest while a 13.604 sees Hartley go second. Moments later Raikkonen responds with a 13.033.
Both Renaults are in the 14.6s, Sainz and Hulkenberg both running the new bargeboards the German tried on Thursday.
Bottas heads off down the escape road at Ste Devote and as he spins the car around brushes the barriers with his rear wing. He subsequently heads to the pits.
Following his installation lap, Ricciardo's crew is working on the car's front suspension.
Raikkonen improves to 12.978 as Hamilton goes third (13.224), ahead of Gasly, Hartley, Bottas and Sainz.
A 12.696 sees Hamilton go quickest, as Vettel consolidates his third place with a 13.108.
After 15 minutes, all bar Vandoorne, Sirotkin and the Bulls have posted times.
Ricciardo heads out as the rear wing is changed on Bottas's car.
Vettel bangs in a 12.482 then promptly pits. Moment later, on his first flying lap, Ricciardo casually posts a 12.449.
"There is no grip from the whole chassis," complains Grosjean. He then fires off some abuse in the direction of Leclerc.
Replays show Gasly and Hartley both getting worryingly close to the barriers.
On his first flying lap Verstappen posts 12.336 to make it a Red Bull 1-2.
Moments later, Ricciardo responds with a 12.237 as Vandoorne goes seventh with a 13.191.
"Oh seriously boys, seriously," says Grosjean, the Haas driver unhappy with everything, his car, other drivers and the failure of Charlie Whiting to respond to his calls.
Already, Verstappen is getting close to Thursday's pace, the Red Bull driver going quickest with an 11.990 before improving to 11.787, almost half-a-second quicker than his teammate.
In the Haas garage, following his complaints, the crew are changing the front and rear suspension on Grosjean's car. The Frenchman is currently last (14.850) while teammate Magnussen is 17th (14.192).
Ricciardo improves to 11.920 but remains second.
A 12.264 sees Raikkonen go third, albeit 0.477s off the pace.
Bottas runs wide in the chicane after being caught out by a very rapid Verstappen.
Another improvement for Raikkonen who is now 0.355s off the pace.
At half-time, along with the usual suspects we have both Toro Rossos, both Renaults and a McLaren (Vandoorne).
Despite a poor final sector, compromised by Sainz running wide in T1, Vettel improves to third with a 12.023.
Rather than follow Bottas' example and spin the car around at T1, Sainz executes as three-point turn... indeed, a six-point turn.
The Mercedes duo are back on track on fresh hypers as attention turns to qualifying sims.
Bottas posts PBs in all three sectors, going fifth with a 12.356. Posting a PB is S1, Hamilton subsequently eases off and abandons the lap.
Ahead of his next flying lap, Bottas is advised that there was "a lot of overheating" at the end of his previous flyer.
At his third attempt, Hamilton posts PBs in the first two sectors, finally crossing the line at 12.273 to go fifth, albeit 0.486s off the pace.
As Bottas fails to improve he is told to cool his tyres and focus on settings, his tyres still overheating to a worrying extent.
Desperation at Williams, no sooner has Stroll complains of understeer and lack of torque than he's off at T1. Like Verstappen on Thursday he opts to reverse back on to the track.
A lock-up for Grosjean at Mirabeau, as Hartley and Gasly consolidate seventh and eighth.
Game over for Verstappen as he hits the barriers on the exit of the Swimming Pool on the approach to Rascasse. The RB14 has incurred significant damage to its right-hand side.
The session is red flagged.
As the Dutchman is told "better now than this afternoon", replay suggests Verstappen might have been put off by a very slow Sainz in the swimming pool section.
"Pace is still there Nico," Hulkenberg is told as he fails to improve on 14th (13.112), "it's just traffic, that's Monaco."
The clock continues to count down, and as the session is green-flagged there are less than 3 minutes remaining.
Unperturbed by his teammate's fate, Ricciardo is quickest in the final two sectors, raining the bar with an 11.786, just one-thousandth of a second quicker.
Stroll is unhappy with his rear, the Canadian down in 16th while teammate Sirotkin is currently 10th.
Going quickest in S2, Ricciardo looks as though he might raise the benchmark ever higher, but a slowing Toro Rosso causes him to back off.
There are no other significant improvements.
Ricciardo is quickest, ahead of Verstappen, Vettel, Raikkonen, Hamilton, Bottas, Hartley, Gasly, Sainz and Sirotkin.
Vandoorne is eleventh, ahead of Ocon, Perez, Hulkenberg, Alonso, Stroll, Leclerc, Grosjean, Magnussen and Ericsson.
Check out our Saturday gallery from Monaco, here.