While it was forecast that it would rain for much of the day, and FP3 was certainly compromised by the weather, things have much improved over the last couple of hours and it looks as if qualifying might be bathed in sunshine.
While this ends any hope of the sort of mixed up, lottery style grid we might have hoped for, it should at least allow us to see the true pecking order in terms of outright pace.
Though this morning's session will show the Ferrari duo as having achieved a 1-2 this was all about Vettel and Raikkonen making a late switch from Inters to slicks and not a sudden revival rom the Maranello outfit.
Other than the big three, if conditions remain good we may at last get to see how the midfield is panning out, with some teams appearing to be keeping their cards close to their chests in pre-season testing and others experiencing various "issues".
Ahead of Q1, the air temperature is 24 degrees C, while the track temperature is 32 degrees. There is a 30% chance of rain.
The lights go green and in no time at all there are 11 drivers on track, including both Force Indias, the Panthers opting not to run in FP3. All are on the ultras.
Hulkenberg gets things underway with a 25.348, but this is soon beaten by Grosjean who crosses the line at 24.967.
Sainz posts 24.655 and Perez 24.914 as Vettel complains about being blocked by a Williams.
No such problems for teammate Raikkonen who goes quickest with a 23.616, Vettel posting 23.921 to go second. The German was quickest in the final sectors despite running wide in the final corner and losing time to the Williams in S1.
A 23.802 sees Hamilton split the Ferraris, the Briton hanging out the rear of the Mercedes in T15.
Bottas goes second with a 23.765 as the crowd rises to cheer Ricciardo as he begins his first flying lap.
Raikkonen consolidates his top spot with a 23.096 as Ricciardo goes second with a 23.509 and teammate Verstappen third on 23.756.
Hamilton posts PBs in the final sectors and as a result can 'only' manage 23.263 which puts him second.
Alonso goes seventh with a 24.480, 1.384s off the pace and, at this early stage, best of the rest.
The first runs completed, Gasly, Stroll, Hartley and the Saubers comprise the drop zone.
As Hamilton is advised that he's losing out in S2, Vettel goes quickest in that sector, crossing the line at 23.348 to go third.
Both Saubers improve, Leclerc to 19th and Ericsson to an impressive 12th (24.873).
Hamilton takes the top spot with a 22.824, 0.272s clear of Raikkonen, as the Toro Rosso duo are clearly struggling.
PBs in all three sectors see Grosjean go sixth (23.671) as teammate Magnussen, currently 14th seeks to improve. The Dane subsequently posts 23.909 to go 8th.
Perez improves to tenth with a 24.344, the Mexican subsequently joined by his teammate who posts 24.503 to go 11th.
With less than a minute remaining, Sirotkin, Stroll, Leclerc and the Toro Rossos are still in the danger zone with Ericsson and Vandoorne hovering.
Stroll posts 24.464 to go 12th but he is demoted by Vandoorne and despite a brave, brave effort Hartley can only manage 16th. Nonetheless, Stroll survive in 14th to contest Q2.
Hamilton is quickest, ahead of Raikkonen, Vettel, Verstappen, Ricciardo, Sainz, Alonso, Grosjean, Bottas and Hulkenberg.
We lose Hartley, Ericsson, Leclerc, Sirotkin, and Gasly, who had an off on his final charge and went off into the gravel.
So, while we wait to see the true pace of the leaders, it is clear that Toro Rosso and Sauber have much work to do.
The lights go green for Q2 but there is no immediate rush to action. Eventually Verstappen heads out, the Red Bull sporting a set of supersofts. Other drivers head out but most are on the ultras, though Ricciardo follows the example of his teammate.
Verstappen posts 22.830 but Raikkonen crosses the line at 22.507 moments later.
Once again, Vettel is out-classed by his teammate this weekend, the German posting 22.645 to go second. However, a 22.051 from Hamilton demotes the pair of them.
Bottas can only manage 22.659, which while better than the Red Bulls leaves him 0.608s off his teammate's pace.
A big lock-up for Hulkenberg in T1 leaving the German with a painful looking flat-spot.
Alonso goes seventh with a 23.692 ahead of Sainz and Magnussen.
While Hamilton pits, Bottas stays out for another lap and manages to improve to fourth with a 22.659, but he still remains 0.608s off the pace. That's compared to Verstappen and Ricciardo who were 0.779s and 0.846s off the pace on supersofts.
With under four minutes remaining, Stroll, Grosjean, Perez, Hulkenberg and Ocon comprise the drop zone.
Alonso queries the weather outlook, claiming that the sky is getting darker and therefore he wants to head out as soon as possible. Could be the Halo casting a shadow.
All are back on track, the Red Bulls sticking with their supersoft tyres.
Grosjean improves to seventh, with Magnussen leapfrogging him moments later.
Hulkenberg goes ninth, thereby demoting his teammate.
Vandoorne fails to improve while Bottas posts 22.089 to go second.
Sainz improves to seventh which drops Alonso to eleventh.
At the death, Vettel bangs in a 21.944 to go quickest by 0.107s.
So, Vettel quickest, ahead of Hamilton, Bottas, Verstappen, Raikkonen, Ricciardo, Sainz, Magnussen, Grosjean and Hulkenberg.
We lose Alonso, Vandoorne, Perez, Stroll and Ocon.
Told he only managed 11th, Alonso takes it remarkably calmly. "It's good, it's OK," says the Spaniard.
Looking ahead to Q3, while the battle between Ferrari and Mercedes is centre stage, particularly Vettel and Hamilton, it is the pace of the Red Bulls which is really interesting, the Austrian outfit clearly feeling that an opening stint on the red-banded rubber tomorrow will pay off.
The lights go green and in moments the front-runners are back on track. All are on ultras.
The session is red flagged when Bottas hits the wall at T2 after running wide in T1.
The right-hand side of the W09 is badly damaged, and as the camera cuts to the Mercedes garage Toto Wolff is clearly not impressed.
The clock is stopped with 9:47 remaining.
He hits the wall with the right-rear of the car before hitting it again with the front right. All four wheel-tethers do their job but one would be surprised if the Finn doesn't need a new gearbox... amongst other things.
As is standard practice these days, Bottas is taken to the medical centre as a precaution though it will be his damaged pride that actually requires attention.
Check out our Saturday gallery from Melbourne, here.
Ahead of the all-clear, Ricciardo waits patiently at the end of the pitlane.
Drivers are warned of the slippery track surface in T2
Hamilton passes Ricciardo on their out-lap, the Briton aware that he won't have Bottas riding shotgun tomorrow.
Hamilton goes quickest in the first two sectors, but Vettel goes slightly quicker in S1.
Hamilton crosses the line at 22.051 while Ricciardo goes second and Verstappen third.
Vettel is quickest in the first two sectors but loses time in S3 and crosses the line 0.034s down on the Briton.
Raikkonen goes fourth with a 22.251, splitting the Bulls, while Sainz, Magnussen, Grosjean and Hulkenberg are only going for one hot lap.
In their eagerness to get back on track, Grosjean and Sainz are scrapping for position in the pitlane.
All nine are on track for the final assault, Hamilton leading the way... in every sense.
The Briton goes quickest again in S1, maintaining the pace in S2. He crosses the line at a mighty 21.164 as Raikkonen improves to second (21.828) and Vettel remains third.
Ricciardo momentarily leapfrogs his Red Bull teammate only to be promptly demoted again.
It's purple all the way for Hamilton, with his rivals only able to manage PBs.
Despite that brief moment from Vettel it's pretty much business as usual, Hamilton digging deep, turning up the engine modes and finding a mighty 0.664s advantage. Had Bottas not made that mistake it would almost certainly have been another front-row lock-out.
Hamilton starts from pole, ahead of Raikkonen, Vettel, Verstappen, Ricciardo, Magnussen, Grosjean, Hulkenberg, Sainz and Bottas.
While Alonso starts eleventh, ahead of Vandoorne, Perez, Stroll, Ocon, Hartley, Ericsson, Leclerc, Sirotkin and Gasly.
"My heart's racing," admits Hamilton in the moments after the session, "I wish you could feel it right now.
"I'm so grateful to the Aussies having us here every year," he adds, "I'm so happy with that lap it was such a nice lap. I'm always driving for perfection and that's as close as I could get."
"It was pretty decent job," adds Raikkonen, "but obviously the lap time difference is still quite big.
"It wasn't a straight forward session with the weather this morning and the disturbance," he adds, referring to the red flag. "We have to be happy with where we're starting, but there's still a lot of work to be done. But not too bad."
"Yesterday I wasn't happy," admits Vettel, "but today it kept coming.
"I had a moment in Turn 13," he admits, "I tried to brake too late.
"Let's see what happens tomorrow. I think it's very close in the long runs so let's see, who knows, we'll have an opportunity at the start. It's a good result for the team."
Check out our Saturday gallery from Melbourne, here.