Ahead of today's second practice session the air temperature is 18.2 degrees C, while the track temperature is 21.8 degrees. It remains overcast and cool. There is a 40% chance of rain.

Carlos Sainz led a Ferrari 1-2 in opening practice, a session which began and ended in the wet and suffered a red flag period when Kevin Magnussen stopped on track.

The Dane was one of several drivers to encounter a technical issue, with Valtteri Bottas sidelined for much of the session as was Esteban Ocon.

New engine components mean that six drivers face grid penalties, among them Max Verstappen and Charles Leclerc who will start from the back of the grid.

In terms of updates, Mercedes has a new front wing endplate, floor fence and edge, together with new rear wing flap and tips, while Red Bull has a new engine cover and rear wishbone shroud and Ferrari a new rear wing and beam wing.

McLaren has a new diffuser, rear wing, beam wing, rear brake winglet, engine cover, cooling louvres and front trackrod fairing, while Alpine has new rear brake ducts and floor fences and Alpha Tauri a new rear wishbone shroud, rear brake winglets, rear wing and beam wing.

At Aston Martin there are new front wing flaps and a new rear wing, while Williams has new front wing flaps, rear wing flaps and beam wing.

Alfa Romeo has new front wing flaps, rear wing flaps and endplates, and Haas new rear brake winglets and beam wing.

The lights go green and Zhou leads the way, followed by Bottas, Stroll, Vettel and Sainz. All are on mediums bar Bottas and Vettel who are on hards. Schumacher emerges on softs.

"Track is a bit more damp than expected," reports Sainz. Perez concurs.

Zhou posts a 50.637, Stroll a 50.938 and Albon a 50.093, only for Sainz to stop the clock at 48.818. Perez goes second with a 49.158.

A 47.699 sees Verstappen go top by over a second.

As replay shows Sainz getting very frustrated at a slow Vettel, teammate Leclerc locks-up and runs wide at Turn 6.

The Monegasque subsequently goes second with a 48.152, ahead of Sainz, Alonso and Perez.

Sainz runs wide at Turn 13, subsequently going on to post a 34.390. "Nice bit of rally," he says of his excursion.

"My tear off is stuck in the right suspension," warns Verstappen, despite which he raises the bar with a 46.928.

"I can't get any temp in the tyres," complains Russell who is currently 16th. Teammate Hamilton is 10th.

Tsunoda goes fifth with a 48.331, ahead of Norris, Zhou, Ricciardo and Alonso.

Just over twenty minutes into the session and Gasly, who handed his car over to Liam Lawson in FP1, is the only driver on track.

Leclerc complains about the noises from his steering wheel toggles, admitting that they sound like engine noises. The Monegasque is clearly not entirely confident.

In the Red Bull garage, a new rear wing is being fitted to Perez' car.

As the majority switch to softs, Verstappen raises the bar with a 45.507, while Leclerc can only manage a 46.369.

Hamilton improves to sixth (46.893) and Russell seventh (47.042).

As in FP1, Stroll is looking good, the Canadian improving to fourth with a 46.635. The Aston Martin driver (heir?) warns that he is starting to see drops of rain.

Norris has to go off track in order to pass a very slow Stroll at the old Bus Stop.

Alonso improves to seventh with a 46.975.

Down in 16th, Perez has yet to try the red-banded rubber. Thus far he has only completed 7 laps, as has Norris, while Latifi has completed 9.

Gasly runs wide at Les Combes, the Frenchman currently 13th (47.782). "I'm not sure what happened," he admits, "I lost the rear."

With just over 17 minutes remaining, as Verstappen, Stroll and Sainz switch to mediums, and Hamilton to hards, it begins to rain.

Sticking to slicks, albeit hards, Hamilton gets it all wrong at Les Combes, while elsewhere Leclerc runs wide.

In quick succession, Leclerc and Hamilton have worrying twitches through Eau Rouge.

"It's raining quite a bit here now," warns Norris as he becomes the latest to fall foul of Les Combes.

Moments later Schumacher takes a long trip through the gravel trap at... yep, Les Combes. "It's super hard to recognise where the wet patches are," admits the German.

Not wanting to take any unnecessary risks, Mercedes calls both drivers in. Indeed, with 6 minutes remaining there are no drivers on track.

With three minutes remaining, the Aston Martin pair head out, both on wets. They are followed by a number of drivers, most of whom are on Inters though a few are on slicks.

The mad flurry of activity is so that the drivers can perform their practice starts, however in the melee the stewards feel that Verstappen carried out his start in the wrong place and are investigating.

The session ends. Verstappen is quickest, ahead of Leclerc, Norris, Stroll, Sainz, Hamilton, Alonso, Russell, Ricciardo and Perez.

Albon is eleventh, ahead of Zhou, Tsunoda, Gasly, Vettel, Ocon, Magnussen, Bottas, Latifi and Schumacher.

Check out our Friday gallery from Spa here.