Valtteri Bottas has been for a splash about on the track but no sign of Lewis Hamilton or either Red Bull drivers yet. Sebastian Vettel is also biding his time.

Andrew Benson
BBC Sport’s chief F1 writer in Melbourne

McLaren are under the spotlight this weekend, after a difficult pre-season and with expectations high after their switch to Renault engines and their claims last year that their car was on a similar level to the Red Bull.

Friday did not go well. Both cars had exhaust leaks in the first half of the session, losing time, and Fernando Alonso ended the day 1.1secs off the quickest Red Bull. “We will get better and better, that’s for sure,” Alonso said.

They’re going to have to if they are going to stop the pressure becoming uncomfortable.

Image source, Getty Images

It's still very warm in Melbourne and the track is drying quickly. Fernando Alonso is seeing how inters handle the conditions.

Evelyn: Currently trying to stay dry at turn 16 in the Senna stand...wind is very cold...

Jolyon Palmer
Former Renault driver

It's slippery conditions, everyone is on the full wets and no-one wants to take a risk with the car. I think it will be a while yet before the track if fully driveable.

Valtteri Bottas, Stoffel Vandoorne, Romain Grosjean and Brendon Hartley also head out to test the conditions on the wet tyres.

Image source, Getty Images

Assuming Lewis Hamilton does the business once again in the wet, how much do you think he will take pole position by?

Fraze: I'd say somewhere between 0.2 and 0.6s, assuming his doesn't bin it... which I hope he doesn't do.

Jennie Gow
BBC Radio 5 live pit-lane reporter

Gearbox issue for Lance Stroll. They will be hoping to get him out at some stage in the session.

Final practice is under way as Nico Hulkenberg heads straight out onto the circuit on full wets.

You can listen to audio commentary online via this page right now.

Image source, Getty Images

Image source, F1.com

Not sure these guys got the memo about the weather forecast for today. Shorts? Really?

Anyway, they've been hard at it sweeping the standing water off the track as the drivers get in their cars ready for one hour of final practice.

Fancy playing Lewis Hamilton pole bingo? We know he revels in the wet so assuming he masters the conditions once again, just how much quicker than the rest of the field do you think he will be in qualifying?

Get involved #bbcf1

Image source, EPA

Last year was a disastrous race for Daniel Ricciardo. The Australian started his home grand prix from the pit lane after his car stopped on the way to the grid and he then retired 25 laps in.

This weekend hasn't started particularly well because he's been hit with a three-place grid penalty for tomorrow's race for a red-flag infringement in yesterday's practice.

It's not been easy to pick out some quotes from Ricciardo about the penalty that did not contain swear words, but here's a bit of what he had to say.

“I made a mistake, no doubt about it, but is that mistake worth a grid penalty in a practice session when no car’s on track, no-one’s upside down," he told Australian network Ten., external

“It was a cable on the track. I didn’t pass the incident. I just think common sense should have prevailed.”

Here's the latest forecast from BBC weather guru Ian Fergusson. Basically rain. And lots of it.

Andrew Benson
BBC Sport’s chief F1 writer in Melbourne

Image source, Getty Images

The first race is always marked by great anticipation, as the true competitiveness of the cars finally emerges bit by bit over the weekend. Friday was a day of contrasting moods. After first practice, it appeared as if Mercedes might be set for a walkover, but second practice told a different story. On both short runs and long, the top three teams were extremely closely matched.

If it stays wet on Saturday, it would mean a clear picture of absolute qualifying pace does not emerge this weekend but so far the auguries are good for a competitive season.

Mercedes' Lewis Hamilton posted the quickest time in second practice but just 0.283 seconds separated the top three teams.

Hamilton was 0.127secs clear of Red Bull's Max Verstappen, although the world champion looked as if he had more potential had he not lost time on his quickest lap.

The world champion's team-mate Valtteri Bottas was third, from the Ferrari of Kimi Raikkonen.

This was the scene a couple of hours ago. The rain has eased a little with one hour of final practice getting under way at 03:00 GMT. That's a touch under 15 minutes away.

Jacqui Baker Stubbs: Hope you brought your rain gear to sunny Melbourne @bbcf1, external. Looks like we are getting a summer of rain in a day, plus lightning!! #bbcf1, external@Jack_Nicholls, external@JennieGow, external

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Andrew Benson
BBC Sport’s chief F1 writer in Melbourne

Image source, Getty Images

Melbourne looks a very different place on Saturday.

Thursday and Friday were all blue skies and warm sunshine. The warmth has remained, but the blue skies have been replaced by grey, and they are pouring down rain.

For the city of Melbourne, it is good news - a local journalist was saying the other day that it has not rained here since the first day of the Australian Open tennis in January. And drought is a real concern. And of course, Formula 1-wise, rain always spices things up.