Ahead of today's qualifying the air temperature is 15.1 degrees C, while the track temperature is 20.3 degrees. It remains, cool, overcast and damp. The risk of rain is 30%.

We've missed out the words ' all important' because although this session is important, such are the number of grid penalties which mean the likes of Verstappen and Leclerc will start from the back, it is almost impossible to predict what's going to happen or who will end up where.

In this morning's practice session, Perez and Sainz were both well placed, which is just as well for as it stands they remain their teams' main hopes.

The cooler conditions mean that Mercedes is unable to get the best out of its tyres, which suggests the German team might not be in a position to capitalise on those penalties.

Then there's the weather, with rain possible both this afternoon and tomorrow.

All-in-all this really is one session where anything can and probably will happen, consequently rather than over analyse it might be best to just sit back and enjoy the ride.

Adding to the fun and games, the start of the session is delayed as repairs to the safety barriers are required following a crash during one of the support races.

Eventually, race control confirms that Q1 will get underway at 16:25 (local time).

The lights go green and Latifi (mediums) leads the way. He is subsequently joined by Schumacher, who is on softs.

As Latifi begins his first flying lap, he and Schumacher are the only drivers on track.

In fact, Latifi pits without posting a time and as Schumacher posts a 47.929, this is the signal for the rest to head out. Soon all 20 drivers are on track, all on softs.

Russell and the Bulls trade fastest sectors.

Hamilton crosses the line at 46.703, but this is soon beaten by Magnussen and then Russell (46.269).

Perez goes quickest with a 45.377, ahead of Leclerc and Norris, only to be eclipsed by Sainz (45.050) and then Verstappen (44.581).

"Make sure we don't give anyone a tow," Hamilton is warned.

Russell expresses his dissatisfaction with Tsunoda's antics.

Ocon goes fifth and Alonso sixth, as Hamilton slips to 15th.

Russell's second flying lap sees him fail to improve, while Hamilton goes eleventh with a 46.308.

The Mercedes pair head back to the pits to prepare, like their 18 rivals, for the final assault. Stroll, Latifi, Schumacher and the Alfa pair comprise the drop zone.

The Bulls and Ferrari drivers don't look as though they will run again.

Ricciardo is warned of the possibility of "queuing" in S3, however, no issue for Latifi who was first out.

Lots of PBs in S1 but no purples.

Latifi goes 13th but is it enough.

Stroll goes tenth, Schumacher 13th, while Bottas pits. Zhou goes seventh, as Vettel goes 15th.

Ricciardo goes 5th with a 46.033, but is demoted by his teammate who posts a 45.475.

In quick succession, Russell goes fifth, Albon sixth and Hamilton seventh.

However, Ricciardo has his time deleted, as does Tsunoda.

Quickest is Verstappen, ahead of Sainz, Perez, Leclerc, Russell, Albon, Hamilton, Norris, Ocon and Alonso.

Hamilton is first out for Q2, followed by his Mercedes teammate. Next out is Perez, followed by Sainz, Schumacher and Norris.

Out front, Hamilton is obviously posting purples, but behind Verstappen is a lot quicker.

Hamilton crosses the line at 46.622, while Russell posts 46.284.

However, Verstappen, on used softs, goes top with a 44.723, ahead of Perez (44.794), Sainz, Norris and Alonso.

A 45.475 sees Ocon go fourth, as Leclerc begins his first flying lap.

Ricciardo has yet to appear.

Despite a tow from his teammate, Leclerc can only manage sixth (45.637).

"The car is jumping like crazy in the apex of slow corners," warns Leclerc.

It wasn't just Verstappen on used rubber for that run, quite a few other drivers were on old rubber, consequently we should see some surprises on the final run.

Ocon leads field back out, Ricciardo finally heading down the pitlane also.

The Bulls sit tight, clearly happy with their 0.6s advantage.

Alonso is getting a two from his teammate, and overtakes on the run up to Les Combes leaving him in free air.

Albon goes quickest in S1, courtesy of a tow from the Mercedes pair.

Alonso goes fifth, Gasly eighth and Zhou ninth.

A 44.551 sees Leclerc go top, while Ricciardo goes eighth.

Hamilton goes fifth and Russell sixth, while Albon goes tenth, thereby demoting Ricciardo to the drop zone.

Gasly baffled by Williams speed on the straights.

Quickest is Leclerc, ahead of Verstappen, Perez, Sainz, Hamilton, Russell, Ocon, Alonso, Norris and Albon.

We lose Ricciardo, Gasly, Zhou, Stroll and Schumacher.

Check out our Saturday gallery from Spa here.