Ahead of today's second practice session, the air temperature is 15.8 degrees C, while the track temperature is 21.8 degrees. It's warmer than earlier, but it's worth noting that the wind has picked up also.
Max Verstappen led a Red Bull 1-2 in the opening session, though in all honesty the session is unlikely - hopefully - to reflect what we can expect for the remainder of the weekend.
The hardest tyres in Pirelli's range, combined with cool temperatures, a new track surface... and the fact it was 'washed' first thing this morning, meant that for much of the session it was like "driving on ice".
Indeed, a large damp patch on the main straight, just before Turn 1, saw a number of drivers with spin or run wide.
While conditions are set to improve over the course of the weekend - and assuming the track doesn't get cleaned again - should drivers continue to struggle, if only due to the choice of compounds, then along with Red Bull, Ferrari and AlphaTauri are looking good, certainly based on this morning's evidence.
The lights go green and Giovinazzi gets things underway, followed by his Alfa teammate. Clearly the Italian team is splitting strategies for Giovinazzi is on hards and Raikkonen mediums.
Bottas and Ricciardo also head out, both on mediums.
The first wave sees Bottas post a 38.443, ahead of Raikkonen, Ricciardo and Giovinazzi, at which point more drivers head out on a mixture of mediums and hards.
Onboard with Sainz reveals that the McLaren driver is still struggling for grip.
Bottas improves to 35.107, just off Verstappen's FP1 pace.
Vettel goes second (36.781) but is leapfrogged by former teammate Raikkonen (36.627), as Hamilton heads out.
The world champion posts 43.232 to go 11th, as Perez goes fourth, ahead of Stroll, Sainz and Leclerc.
As he goes second (35.544), Leclerc questions his team's strategy. "Why are we going slow, push, slow, push," he asks, "why not just push?"
Meanwhile Bottas posts a 34.300, while a 34.644 from Hamilton suggests it is 'business as usual'.
That said, no sooner has Verstappen gone top with a 33.648 than Leclerc posts a 33.429.
The top ten times have all been posted on the mediums.
A 33.543 sees Albon go second, but moments later Bottas posts 33.273 and Verstappen 32.836. Lap after lap the track appears to be improving.
"There is something wrong," reports Ocon, "I'm going flat-out but I'm being overtaken like I was not there." He is advised that the medium runners are around four seconds quicker.
Albon ups the ante with a 31.916 as Grosjean spins in Turn 7.
"I don't want to use those tyres anymore today," sighs the Frenchman.
A change of nose and front wing for Verstappen as Leclerc goes quickest with a 31.540.
Moments later Albon responds with a 30.872. Early days, but has the cat-loving Thai finally rediscovered his mojo?
A 31.514 from Verstappen once again sees a Red Bull 1-2.
Perez (33.831) is currently best of the rest, ahead of Raikkonen, Sainz, Stroll and Vettel.
Yet to post a time, 24 minutes in Latifi heads out on softs, as Kvyat also switches to the red-banded rubber.
Quickest in the two opening sectors, Albon eases off in S3 and finally aborts the lap, as teammate Verstappen reports graining.
Quickest in the final sector, Hamilton posts 31.508 to split the Bulls.
"The brakes are gone," reports Kvyat who is actually on hards not softs.
And talking of softs, Vettel switches to the red-banded rubber.
On the softs, Vettel improves from eleventh (34.567) to sixth (32.680), as more drivers switch to the compound.
Also on softs, Leclerc has a poor opening sector, and subsequently aborts the lap.
Though it is early, the softs isn't showing the same leap forward as the mediums.
More drivers switch to the soft including pace-setter Albon.
"The softs are bad," says Leclerc, "they grain so quickly."
McLaren however is sticking - no pun intended - with the hards, certainly in the case of Norris.
Despite his unease with the softs, Leclerc goes quickest with a 30.751.
No sooner has Albon gone quickest (30.127) than his timer is deleted for running wide in Turn 1.
At half-time, it's: Leclerc, Vettel, Albon, Hamilton, Verstappen, Bottas, Gasly, Sainz, Russell and Grosjean. The Mercedes pair and Norris have yet to try the softs.
Albon - on his sixth lap on this set - posts a 29.627 and finally it's legal, the Thai youngster 0.197s clear of Leclerc.
"The front-right is ripping apart," warns Sainz.
Told that he is the quickest on hards, Norris responds: "I am now, I've just done a whole race stint on that tyre".
Albon consolidates his top spot with a 29.363, as Verstappen goes quickest in S1. The Dutchman stops the clock at 29.370, just 0.007s off his teammate's pace.
A clean sweep for Kvyat who has his time deleted for running wide in both Turn 1 and Turn 14.
Leclerc improves to 29.380 as the top three are covered by just 0.017s.
At which point the Mercedes pair bolt on the red-banded rubber.
"I flat-spotted my front-left," reports Vettel, and indeed, he did, the replay revealing a massive lock-up in Turn 12 which saw small chunks of rubber explode from the offending tyre.
Verstappen crosses the line at 28.984 only to be demoted when Leclerc stops the clock at 28.731.
Hamilton improves to fourth with a 29.902 as Sainz reports that his left mirror is broken.
And just like that, Verstappen reclaims the top spot with a 28.330.
No sooner has Hamilton improved to third than teammate Bottas pops in a 28.905 to push him back down to fourth.
"Front-right opening up," reports the Briton.
With just under 30 minutes remaining there's a brief lull, and once the action resumes the Williams pair indulge in s pot of synchronised spinning, albeit at different corners. "The snap in Turn 8 is a joke," snaps Russell.
Check out our Friday gallery from Istanbul, here.