Ahead of today's sole practice session the air temperature is 24.7 degrees C, while the track temperature is 44.5 degrees. It is bright, sunny and very warm.

In case you've been living in a cave for the last couple of months this weekend we see a new format being trialled.

Following this afternoon's practice session there will be a one-hour qualifying session. The order at the end of qualifying will decide the grid for tomorrow's inaugural Sprint Qualifying - in reality a race - and the finishing order of that will decide the grid for Sunday's race.

With just the one hour before qualifying - as opposed to the usual three - there are no reserve drivers on duty.

Indeed, such is the layout of the new format, nobody can afford any mistakes, be it a technical issue, an off or, God forbid, a red flag.

Sainz heads the queue at the end of the pitlane as the lights go green.

In no time at all there are 18 drivers on duty, a mixture of hards and mediums.

The crowd cheers as Hamilton heads out, leaving Stroll and Bottas as the only drivers still to appear. Indeed, moments later the pair emerge, meaning that all 20 are on track.

Sainz posts the first time of the weekend, an exploratory 35.241.

Corners 9 and 15 - Copse and Stowe - are the two corners where track limits are being watched very carefully.

Of the first wave, Hamilton goes quickest (30.048), ahead of Verstappen (30.274), Gasly, Alonso and Ocon. The Briton is on mediums while the championship leader is on hards. Vettel and Stroll pit without posting times.

Bottas improves to 5th (30.766), only to be demoted when Tsunoda posts a 30.758.

Perez goes third and Russell ninth, as Mazepin is the first driver to have his time deleted.

Having posted a PB in S1, Hamilton runs wide at Copse and subsequently aborts the lap.

Stroll goes 10th with a 31.169, while teammate Vettel goes 8th (30.838).

A 29.861 sees Bottas (mediums) go top only for Hamilton to respond with a 29.690.

Mercedes has a number of updates this weekend, mainly around the bargeboard area, floor and diffuser.

Stroll improves to seventh, behind his teammate, and ahead of Alonso, Tsunoda and Gasly.

A 30.154 sees Ocon improve to third.

Both Mercedes drivers improve, but Bottas' 29.373 sees the Finn go top.

At which point, Perez (mediums) responds with a 28.855.

Verstappen, who has pitted after just one lap, has slipped to sixth, behind Vettel. At which point the championship leader heads out again, this time sporting mediums.

Quickest in all three sectors, the Dutchman crosses the line at 28.179, eclipsing the Mercedes pair by over a second on the same compound.

Talking of tyres, this week the teams are using the new construction rear tyres introduced by Pirelli in the wake of the Baku failures.

Perez closes to within 0.326s of his teammate with a 28.505.

Verstappen complains of no power in the last two corners, though he adds a couple of expletives to hammer home his frustration.

Despite his lack of power, Verstappen improves to 27.745, one again going quickest in all three sectors.

"Who is in front," asks a clearly frustrated Alonso. Told that it is Gasly, he responds, "Okay, god to know."

25 minutes in and the Haas pair are the first to switch to the red-banded softs.

A 28.945 from Vettel - on mediums - drops Hamilton to fifth.

Early days - or perhaps not considering the fact that qualifying follows - but both Ferraris are at the wrong end of the timesheet, as are the AlphaTauris and McLarens.

On the softs, Schumacher goes tenth (30.294) and Mazepin 12th (30.679).

Leclerc goes third on the mediums (28.863), as Raikkonen posts a 29.970 to go tenth. Shortly after Sainz goes fifth with a 29.116.

Just after halfway through and Hamilton has completed the most lap (20), ahead of Bottas and Russell(19). Verstappen has completed just 10 laps.

"Blister on front right," reports Hamilton.

The Bulls head out on softs, Perez leading the way.

The Mexican improves to 28.163, though the first two sectors are merely PB and the third off the pace.

Verstappen, on the other hand, goes purple in S1, maintaining the pace at the second split. At the line it's 27.035.

Norris goes third on mediums (28.740), as Gasly goes fifth and Tsunoda 8th, both on the yellow-banded rubber.

A 28.350 sees Ricciardo go third ahead of his McLaren teammate.

Elsewhere, a spin for Sainz in Turn 4 compromises Perez' efforts to improve.

"It was quite dangerous with Giovinazzi there," reports the Spaniard.

No such issues for Norris who goes second with a 27.814.

The Williams pair switch to softs, and with 15:00 remaining the rest are set to follow suit in the coming minutes.

Latifi improves to 10th (29.227) on the red-banded rubber, while teammate Russell subsequently improves to 16th (29.665).

The Mercedes pair head out on softs, as does Verstappen. Hamilton reports a vibration on his current set.

The seven-time world champion goes third (27.815), 0.780s off the pace. Bottas can only manage a 27.997.

Told the gap to Verstappen, Hamilton replies: "Seven-tenths, where did that come from?"

Sainz, currently 12th, posts a purple in the first sector, following up with a PB in S2. At the line the Spaniard posts a 29.078 to go fourth, albeit 0.888s off the pace.

Leclerc goes fourth (27.828) and Vettel 7th (28.062).

With under five minutes remaining, Alonso and the McLaren pair have yet to try the softs.

That said, Norris remains second, albeit 0.779s off Verstappen's best.

Perez, currently eighth, 1.128s off the pace, switches back to hards.

Alonso complains of "weird understeer" in certain corners.

The session ends. Verstappen is quickest, ahead of Norris, Hamilton, Leclerc, Bottas, Sainz, Vettel, Perez, Ricciardo and Ocon.

Gasly is eleventh, ahead of Tsunoda, Giovinazzi, Alonso, Raikkonen, Latifi, Schumacher, Stroll, Mazepin and Russell.

Hamilton and Bottas completed the most laps (30), ahead of Tsunoda and Russell (29) and Ricciardo 28, while Verstappen completed just 23, leaving the teams with comparatively little data ahead of this evening's qualifying.

Check out our Friday gallery from Silverstone, here.