The 22-year-old Canadian staked his claim in enthralling fashion. Heavy rain stretched the session to more than two hours, and even as the weather cleared the standing water combined with the oily bitumen of the freshly laid Istanbul Park circuit to make the track extremely slippery and hard to judge from the cockpit.
Stroll is the first non-Mercedes driver to start from pole this season, with championship leader Lewis Hamilton and title contender Valtteri Bottas starting sixth and ninth respectively in a car that struggled in the conditions.
“I can’t really put it into words right now,” Stroll said. “I’m shocked.
“I was under a lot of pressure - I only had one lap to do it there at the end. I had Valtteri [Bottas] who spun in front of me then I had one lap at the end to do it.
“I had the confidence in the car and I just nailed pretty much every corner and pieced it together nicely.”
Sweeter still was that he bit renowned wet-weather expert Max Verstappen in the faster Red Bull Racing machine by 0.29 seconds.
But Verstappen had rights to feel pole should have been his after comfortably topping the previous two qualifying segments.
But his team switched him off the full wet tyre and onto the intermediate part way through the final shootout, and not only was the RB16 less comfortable on the slicker tyre, but it dropped the Dutchman into slower traffic, hampering his efforts to bring the rubber up to temperature.
“For us the inters were horrible,” a clearly frustrated Verstappen said. “I’m a bit disappointed of course.
“When you’re first the whole time and you come out second it’s not what you want.”
Sergio Perez was third for Racing Point after holding provisional pole for much of Q3, but the Mexican slipped off the track with his final lap to fall behind the late-improving Verstappen and his pole-getting teammate.
“A great result for the team something we were not really expecting,” he said.
“Very pleased - in the end [I was] just unlucky.”
Thai driver Alex Albon qualified fourth for Red Bull Racing after receiving the same tyres as teammate Verstappen. He beat Renault’s Daniel Ricciardo, who will start fifth.
Hamilton will attempt to seal his record-equalling seventh championship from sixth on the grid. The Briton only needs to prevent teammate Bottas, starting ninth, from outscoring him by eight points or more to confirm the title.
Between the teammates will start Renault’s Esteban Ocon and Alfa Romeo’s Kimi Raikkonen in the Italian team’s best qualifying performance of the year, with Antonio Giovinazzi completing the top 10.
McLaren teammates Lando Norris and Carlos Sainz were knocked out 11th and 13th after gambling on the intermediate tyre when the track was too wet in Q2.
Sebastian Vettel split the pair in 12th for Ferrari, outqualifying teammate Charles Leclerc, who will start 14th, for the first time since August.
Pierre Gasly will start 15th for AlphaTauri ahead of Haas driver Kevin Magnussen, who fumed after his Q1 elimination that several drivers ignored double waved yellow flags to improve their times and push him into the knockout zone.
The stewards said they would open an investigation into any breaches of the caution rules after qualifying.
AlphaTauri’s Daniil Kvyat qualified 17th ahead of Williams driver George Russell, though the Briton will start last with a grid penalty for using too any engine parts.
Romain Grosjean and Nicholas Latifi qualified 19th and 20th after both beached their cars in the gravel.