Charles Leclerc stayed at the top of the timesheets as the weather again played a role in second practice at the Italian Grand Prix.
Starting in fully dry conditions, Mercedes set the pace initially as teams conducted the first meaningful running, however, a heavy shower would soon be approaching the circuit.
Before it did, Leclerc would pounce, posting a 1m20.978s, to lead teammate Sebastian Vettel by two-tenths of a second as Ferrari got their low-fuel run in early.
Red Bull likewise moved upto third and fourth with Max Verstappen only 0.3s behind Leclerc as the team used an ultra-low downforce configuration.
While a grid penalty means the Dutchman will start last, teammate Alex Albon offered encouragement being just 0.25s behind in fourth.
Lewis Hamilton and Valtteri Bottas didn't complete a soft tyre run before the rain arrived leading to a lull in the action.
But after 25 minutes, teams re-emerged with only the area around the Lesmo bends proving particularly damp and making competitive times very difficult.
It would soon dry enough for the two Mercedes to complete their qualifying run as Hamilton used a tow from his teammate to take second with Valtteri took fourth, demoting the Red Bulls.
A tight midfield pack would follow led by Pierre Gasly in seventh, but only 0.4s would split the Frenchman to Kimi Raikkonen in 14th.
Toro Rosso look strong, however, with Daniil Kvyat in 10th for the Faenza-based squad.
Romain Grosjean sat eighth with Daniel Ricciardo ninth, though the order was slightly distorted by the changing conditions.
McLaren would slip down after getting both cars in the top three in the morning.
Carlos Sainz was 12th, while Lando Norris, who also starts at the back due to engine grid penalties, only hit the track with 20 minutes to go and would finish 18th.
Racing Point, a team that typically goes well on low downforce circuits, also struggled with Lance Stroll 15th and Sergio Perez, following his crash in the wet first session, in 16th.
After the low fuel runs, focus switched to a race simulation as more light drizzle continued to fall without requiring the need for intermediates.
Despite some fears from the drivers, notably Leclerc, teams were happy to stay out with Ferrari suggesting similar damp conditions are likely on Sunday, making the running particularly useful
The Monegasque found the going tricky though as he opted for a soft, hard strategy for his long run, while Vettel and the two Mercedes ran medium and soft.
Based on their relative pace though, it appears to be a repeat of Spa is on the cards with Ferrari having the edge while Hamilton is fractionally faster on race pace.