Ahead of today's second practice session, the air temperature is 23.9 degrees C, while the track temperature is 32.7 degrees. It remains overcast.
The Mercedes pair set the pace in this morning's session, with both Ferraris over 0.9s off the pace. Even worse, Hamilton's best was set on softs, Bottas' on mediums and the Ferraris were on supersofts.
The Bulls were third (Ricciardo) and fifth (Verstappen), 0.6s and 1.1s off the pace respectively.
Ocon was best of the rest, ahead of Grosjean, Leclerc and Ericsson in a session which saw plenty of activity as drivers feared rain which never arrived, though the threat remains.
Lando Norris was on duty for McLaren, and this afternoon Stoffel Vandoorne gets his car back.
There were a few offs, most notably Fernando Alonso keeping out of the barriers after going off at Degner, while Pierre Gasly has been reprimanded for an incident involving Lewis Hamilton at the final chicane.
When the lights go green, the McLaren pair are first out, followed by Grosjean, all three on the mediums. Vettel heads out on the softs.
Of the first group, Vettel goes quickest, crossing the line at 29.971. Moments later, Raikkonen posts 30.003, while Magnussen goes third on softs and Grosjean fourth on mediums.
Vettel subsequently improves to 29.398 - an improvement on this morning - while Raikkonen fails to improve.
In the Toro Rosso garage, Gasly's car is the centre of some serious attention. Along with the Bulls and Silver Arrows, the Frenchman is the only driver yet to appear this afternoon.
Racing Point is one of several teams to have split its strategy, Perez goes third on the softs while Ocon goes fourth on the mediums.
Fifteen minutes in and the Bulls and Silver Arrows head out, leaving Gasly as the only no show, the Frenchman thought to be suffering a fuel pump issue.
As Ricciardo goes third (30.251) on the softs, Hartley, running the new Honda unit, goes sixth, also on the softs.
A 30.251 sees Verstappen go fourth, only to be demoted when Bottas goes second (29.803), both on the softs.
Hamilton goes straight to the top of the timesheets with a 29.005, like his teammate the Briton is on the yellow-banded rubber.
Vandoorne's McLaren is smothered in flo-vis as McLaren uses every opportunity to learn.
Hamilton improves to 28.911 as Bottas is told he can still find time in Turns 2 and 11.
Hamilton and his engineer discuss whether the Briton wants to do another lap, and a very civilised and polite conversation it is.
Sirotkin is off at Spoon but is able to continue.
"I'm happy to box," reveals Sainz, the Spaniard currently down in 14th.
Around 31 minutes in, Stroll is the first driver to switch to the supersofts, followed by Hulkenberg, Grosjean, Magnussen, Ocon and Vettel.
Stroll improves to tenth (31.215) on the red-banded rubber, with Grosjean going seventh (30.440) moments later.
Vettel goes quickest in S1 on the supers, as Hulkenberg and Magnussen go seventh and eighth overall. Vettel maintains the pace in S2 but can only manage a PB in the final sector, crossing the line at 29.050, 0.139s down on Hamilton.
Also on the supers, Ricciardo consolidates third with a 29.513.
While Ericsson improves to 9th on the supers, Magnussen fails to improve and remains 14th.
Bottas fits a set of supers as we look set to see what Mercedes can do.
A couple of silly incidents, one involving Leclerc and Stroll at the final chicane, while Ocon is angry that after passing Vandoorne the McLaren driver re-passed him.
Unsurprisingly, Bottas goes quickest in S1 however he backs off after running wide exiting the second Degner.
Meanwhile, Hamilton heads out on the supers as Verstappen posts 29.257 to go third.
The Briton goes quickest in S1, maintaining the pace in S2 and S3, crossing the line at 28.217 to go 0.833s clear of Vettel.
Shortly after, despite only going quickest in S2, Bottas improves to second with a 28.678.
While Bottas got two laps out of his supers - sort of - Hamilton pits, feeling they were only good for one hot lap.
Raikkonen fails to improve on the supers, his cause not helped by running wide in the corner before he began his lap.
Behind the big six (three), it's Ocon, Grosjean, Ericsson, Hartley, Perez, Hulkenberg, Sainz, Leclerc and Magnussen. Gasly has yet to appear.
Verstappen told he was "shallow" with his clutch pedal at his launch.
Ahead of the race sims, practice starts are the order of the day.
Never mind red-banded tyres, Magnussen's tyres are green after an off at the final chicane.
With twenty minutes remaining it looks as though Gasly might be finally heading out.
Heading out on the supers, Perez is told the team expects 12 laps from them. However, Vettel has done 14 on his set thus far.
A disagreement between Vettel and his engineer over which corners constitute sector one, the German eventually admitting "my mistake".
Other than Gasly, Alonso remains the only driver yet to try the supersofts.
With fifteen minutes remaining, Gasly finally heads out. He's on the supersofts.
Grosjean has done 17 laps on his supers, while Verstappen, Ocon, Ericsson, Hulkenberg and Sirotkin have done 16 on theirs.
Ricciardo told that Verstappen is approaching and mustn't be held up. "Understood," comes the reply.
As the clock counts down, all 20 drivers are on track.
Gasly goes 14th (30.795), 0.29s down on his teammate who has completed 26 laps.
Race sim pace sees Hamilton quickest, around half-a-second ahead of Bottas, then Verstappen, Vettel and Ricciardo.
The TV cameras pick up on a nasty blister on the left-rear on Vettel's car.
In an incident not entirely dissimilar to this morning, Bottas almost trips up over Gasly at the final chicane.
Having run over the kerb at T9, Sirotkin calls on the team to check his floor.
"Can I box?" asks Bottas following a lock-up which did his tyres no good whatsoever.
The session ends. Hamilton is quickest, ahead of Bottas, Vettel, Verstappen, Raikkonen, Ricciardo, Ocon, Grosjean, Ericsson and Hartley.
Perez is eleventh, ahead of Hulkenberg, Gasly, Sainz, Leclerc, Magnussen, Alonso, Sirotkin, Stroll and Vandoorne.
While Ferrari no doubt has a little in reserve, the fact is that the Ferraris couldn't get close to Hamilton when they were on the supersofts and he was on softs, with Red Bull also struggling to keep in touch.
Though Toto Wolff continues to talk of the threat from Ferrari, and Vettel insists all is not lost, it is looking increasingly as though the German team has this sewn up.
Check out our Friday gallery from Suzuka, here.