Ahead of today's opening session the air temperature is 19 degrees C, while the track temperature is 23 degrees. It is somewhat overcast, and following rain earlier there is the prospect of further rain over the next ninety minutes. Indeed, race control confirms there is an 80% chance of rain.

However, it will take more than that to dampen the enthusiasm of the fans.

There are no reserve drivers on duty today.

The lights go green and with a clear threat of rain - indeed, there are a few spots in the air - there is a flurry of activity and within moments there are ten drivers on track including Vettel and Raikkonen. A mixture of soft and medium rubber.

Soon all bar Verstappen have been out, and then the Sepang winner heads down the pitlane. Indeed, the Red Bulls are on the supersofts.

Bottas posts the first time of the weekend (46.041), but this is soon eclipsed by Ricciardo (32.372) and Hamilton (31.544). And we're still only five minutes into the session.

Sainz appears to have brought the front gate all the way from Faenza, the Toro Rosso sporting a huge sensor rack.

As Sainz reports spots of rain, Hamilton is told that there are indeed a few droplets but the team is happy for him to stay out and get some dry running time.

As Verstappen posts the fourth time of the morning (32.883), and Bottas improves to 31.551, Hamilton posts 31.072.

Both Mercedes drivers are running the new aero package introduced in Malaysia and which Hamilton subsequently rejected.

Grosjean is the first driver to post a time (34.379), as Vettel, Magnussen and Hulkenberg head out again.

Going quickest in all three sectors, Bottas crosses the line at 30.517, the Finn, who has been giving himself a hard time in the wake of his Sepang performance, subsequently running wide on to the grass as he approaches T1.

Vettel posts 32.468 to go second, as Hamilton goes quickest in the first two sectors before finally crossing the line at 30.042.

Verstappen improves to third (3.762), ahead of Ricciardo, Vettel, Hulkenberg, Raikkonen and Perez.

Vettel improves to third, but at 30.641 remains 0.599s off Hamilton's pace, though, like the Briton, he is on the soft rubber.

Twenty minutes in and all bar Sainz, Gasly and Alonso have posted times.

Raikkonen leapfrogs his teammate with a 30.512 to take third, albeit still 0.470s off Hamilton's pace.

Stroll complains that teammate Massa got in his way. Teenagers, eh!

Twenty-six minutes in and Alonso finally posts a time, the Spaniard going seventh with a 31.588 on the supers.

Moments later, Ricciardo posts 31.179 going quickest in all three sectors. That time, albeit on (fresh) supers, is 0.501s quicker than Hamilton's best.

Jeez, even the flo-vis on the Force India is pink.

The Mercedes duo head out, both now on the supers.

Bottas improves to 30.151 on the red-banded tyre but is still 0.610s off Ricciardo's pace. Hamilton, on the other hand, is looking good, and bangs in a 29.377 to take the top spot.

A brief excursion for Verstappen suggests the rain might be falling again. Elsewhere, Magnussen reports an engine issue.

Hulkenberg improves to seventh with a 30.974, the German now on the supersoft.

Haas confirms that Magnussen has a water pressure issue.

Vettel goes second (29.419), just 0.042s off Hamilton's time, on the softs.

As the drivers prepare to hand back their extra set of tyres, Bottas is told that rain is expected within the next ten minutes which means the drivers will probably want to continue running rather than take the usual 'break'.

Current order is: Hamilton, Vettel, Ricciardo, Bottas, Raikkonen, Verstappen, Hulkenberg, Alonso, Grosjean and Palmer.

Despite being unhappy with his rear, Raikkonen posts 29.979 to go fourth. "My rear is not good," he warns, "if anything we've made it worse."

On fresh supers, Wehrlein posts PBs in all three sectors but remains 3.6s off the pace.

Vandoorne leapfrogs his McLaren teammate with a 31.202.

On fresh supers, Verstappen reports a little more rain than before.

Having posted PBs in the first two sectors he looks set to improve when the session is red flagged. Sainz has crashed heavily at T11.

"**** I don't know what happened," he replies when asked if he is OK.

Well, what happened is the he ran over the wet kerb and then the Astroturf when exiting the hairpin and after that it was only going to end one way, the rear of the car kicked out and he headed into the barriers on the inside wrecking the front of the car. A lot of damage to the Toro Rosso but the driver is OK.

With the Spaniard due a number of component changes, and therefore a hefty grid penalty, the Suzuka weekend just took a further turn for the worse for the Toro Rosso driver.

The session resumes at 11:07, after a total stoppage of around 16 minutes.

Ricciardo leads the mad scramble to get back to work, the drivers keen to get stuck into their long runs.

On board with Alonso who gives the viewer the perfect view of a master at work on a real race track.

As the Spaniard improves to tenth, Vettel, now on the supers, goes quickest in S1. He maintains the pace in S2, but has Ericsson ahead of him in S3. Nonetheless, he posts 29.166 to go quickest, despite losing a lot of time in that final sector.

PBs in all three sectors see Magnussen improve to 11th with a 31.216.

PBs for Gasly also but the Frenchman remains down in 18th place, 3.335s off the pace.

"Slow down, slow down," Magnussen is told, "high gear, same problem as before."

Despite the fact that it is spitting with a little more intensity, the drivers stick with slicks.

"Ignore any brake alarms," Raikkonen is told.

With just under 5 minutes remaining, the track is officially declared wet.

As the rain falls ever harder and the fans don macs and head off to find food or merchandise, there are no further improvements.

Vettel is quickest, ahead of Hamilton, Ricciardo, Raikkonen, Bottas, Verstappen, Ocon, Hulkenberg, Grosjean and Vandoorne.

Magnussen is eleventh, ahead of Vandoorne, Alonso, Perez, Stroll, Palmer, Massa, Sainz, , Gasly, Wehrlein and Ericsson.

Check out our Friday gallery from Suzuka, here.