Charles Leclerc made the mode of the early dry running in Saturday's final practice, the Ferrari driver setting the fastest lap on the soft tyre before changing conditions set in.
Alex Albon was once again in the spotlight in FP3, the Williams charger slotting in second just 0.173s adrift from Leclerc, while Aston Martin's Fernando Alonso clocked in third.
Max Verstappen was a lowly P8 in the session, but the Red Bull driver was comfortably fastest on the intermediate tyres in the damp conditions.
After yesterday's glorious opening day of running in Northhamptonshire, things were looking murky on Saturday morning, with the weather radar pointed to a 90% risk of rain for FP3 while cooler temperatures were also in force.
Over at Ferrari, Charles Leclerc was looking to play catch-up after being sidelined from yesterday's second practice due to an electrical issue on his SF-23.
Alonso and Norris were the first to head down the pitlane, but the McLaren driver was ordered to stop his MCL60 just as he reached the exit. A mechanic was rushed over to extract a cooling fan from the rear of the car and then gave the all clear, but the incident was noted by race control.
Verstappen, although on the medium compound tyre, unsurprisingly went top and improved several times. But both Ferraris - led by Sainz and running on the softs - then outpaced the Dutchman.
However, a revitalized Hamilton, also on the soft tyre, leapfrogged the trio before Leclerc temporarily settled the score while lowering the benchmark to 1m27.419s.
Meanwhile, Friday's hero Alex Albon geared up for a flyer as the rain clouds moved in. But the Williams charger was able to lay down an impressive 1m27.592s in the nick of time that slotted the Anglo-Thai racer into P2, 0.173s behind Leclerc.
Damp conditions set in, encouraging everyone to head back to base to ponder their next move. But after a few minutes of quiet and peace, Leclerc, Albon, Norris and Sainz were up for a run on Inters.
Others followed, but after the drizzle subsided everyone reverted to slicks to resume their dry running, although track conditions remained changeable.
That plan was short-lived however, and it was soon back to Inters as the field sought to get a feel for conditions ahead of qualifying.
Keeping track of the lap times, Verstappen was clear of his rivals by about 1.5s on Inters.
The session concluded with no changes to the pecking order, and with Leclerc topping final practice in the early dry running.
But come rain or shine, Verstappen will be the man to watch in a few hours in qualifying.
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