Daniel Ricciardo topped the timesheets in what was a fairly uneventful session earlier.
Well, not uneventful Nico Hulkenberg who stopped on track following an electrics failure or Marcus Ericsson who damaged his floor going cross-country.
Ricciardo edged out Sebastian Vettel by just 0.079s, and while the German suffered traffic in the final sector of his best lap the German was on ultras while the Australian's best time was on softs.
Lewis Hamilton and Valtteri Bottas were fifth and sixth, both over 0.4s off the pace, but neither ran the ultras.
Romain Grosjean was 'best of the rest', ahead of the Renault pair, with teammate Kevin Magnussen tenth.
Following his engine-related DNF in Germany, Ricciardo is running his Monaco engine, while the Ferrari customer teams are running new ICE and MGU-Hs.
Ahead of the session, the air temperature is 30 degrees C, while the track temperature is 54 degrees. Though bright and sunny, there is a 10% chance of rain, with storms predicted for tomorrow.
Having handed his car over to Antonio Giovinazzi earlier, Charles Leclerc is back in the Sauber this afternoon.
Renault reports a "precautionary energy store change" following this morning's stoppage.
The lights go green, and shortly after Magnussen is the first to head out.
The Dane is followed by his teammate and Ericsson.
As more drivers head out they are sporting a mixture of softs and mediums.
Magnussen gets things underway with a 21.072, but this is soon eclipsed by Grosjean who posts a 20.600. Magnussen on the mediums and his teammate on the softs.
A 20.511 sees Stroll go quickest on the softs, as the Ferraris and Mercedes head out. While both Silver Arrows are on softs, Vettel is on soft while Raikkonen is on mediums.
Despite a lock-up caused by a slower car ahead, Vettel posts 18.997, while Raikkonen goes third with a 19.924.
An 18.093 sees Bottas go quickest, with Hamilton posting 17.875 moments later, the Briton quickest in the first and final sectors.
Ten minutes in and all but Hulkenberg, Alonso and the Bulls have appeared.
On the mediums, Raikkonen improves (18.825), thereby leapfrogging his teammate but remaining 0.950s off Hamilton's pace.
Moment later, as Ericsson spins at T11, Vettel improves to third with an 18.758 but is still 0.883s adrift of the leading Mercedes.
Alonso and Ricciardo head out, leaving Hulkenberg and Verstappen as the 'no shows'.
"I have no power," reports Alonso, who is duly told to pit.
Bottas takes the top spot with a 17.868 as Ricciardo goes third (17.885) on softs. However, Hamilton is on a hot lap and subsequently bangs in a 17.587, this following an off at T4 on his previous lap. It's an off similar to Ericsson's in FP1, which caused damage to the floor of the Sauber.
Encountering traffic, including a slow Alonso, Hartley is told to pit, the kiwi advised that he was doing well and had three-tenths in hand.
Quickest in the final two sectors, Verstappen (softs) posts 17.509 to go quickest.
In sixth, Raikkonen is currently the fastest medium runner, albeit 1.3s off the pace.
Verstappen reports that his battery is not charging.
A 17.556 sees Ricciardo go second, 0.047s off his teammate's pace.
Told to maximise full throttle and cool down his tyres, Leclerc dryly replies: "I can't do both."
Hamilton and Bottas are first to switch to ultras, and both are set to improve from the outset.
Bottas remains fourth having lost time in S3 and aborted his lap, while Hamilton suffers a similar issue and remains third. This despite being quickest in S1 and posting a PB is S2.
Now Vettel switches to ultras. The German is quickest in S1, maintaining his pace in S2. Crossing the line at 16.834, having been quickest in S3, the German goes quickest by 0.675s.
With 55:00 remaining, Hulkenberg climbs into his car.
Also on the ultras - and Ferrari power - Ericsson posts 19.043 to go seventh.
"What we're learning so far, Red Bull seems very quick but the latest time from Seb's Ferrari sets them a big challenge...," admits Pirelli.
"Massive, massive understeer," reports Magnussen, "c'mon guys look into it."
Raikkonen makes the switch to the purple-banded rubber, as Verstappen (ultras) posts 16.908.
Sainz goes sixth (18.495) and Gasly seventh (18.518) only to be demoted when Raikkonen posts 17.153 to go third.
Ricciardo leapfrogs Raikkonen with a 17.061, as Grosjean posts 18.168 to go best of the rest.
"I feel like the balance is a bit far out," reports Ricciardo, who is told to pit.
With 45:00 remaining, Hulkenberg finally heads out. His first timed lap sees him go seventeenth (19.324).
"Some spits of rain," reports Hamilton. He is advised that there is a thunderstorm around five kilometres away but that it is moving away from the area.
"I can see the thunderstorm," says Hamilton, "I saw lightning."
Once again, attention shifts to Sunday as the teams begin their race sims.
Vandoorne is off at T45 after running slightly wide exiting T4 and getting a wheel on the grass. He gets going again but claims that he doesn't know what happened... we do, he went on to the grass.
Ericsson reports that Stroll "cut me up completely", adding "I don't think he saw me".
"Honestly, they don't move out of the way those cars," says Vandoorne of no one in particular, "when they come out of the pits."
"It's quite dark here," reports Verstappen, and indeed the sky is much darker.
Behind the 'usual suspects', it's: Grosjean, Sainz, Gasly, Ocon, Perez, Alonso and Magnussen. They are covered by just 0.8s.
"With some clouds on the horizon, the track temperature is now falling rapidly," says Pirelli. "Is this quite literally the calm before the storm?"
Perez unhappy that his being "blocked" by a Renault.
Unhappy with his set-up, Verstappen asks if he can pit to have it changed, however he is told that's a no go as the team needs the tyre data from his current sim.
He's also unhappy with the traffic and ask if he can be found another slot... he can't.
Check out our Friday gallery from the Hungaroring, here.