Leclerc took second in Friday qualifying for Sunday's race, ceding eight tenths to Red Bull's Max Verstappen in Q3 on a drying track.
But as Verstappen was hit with a five-place grid penalty for taking his fifth gearbox of the season, one more than is allowed, Leclerc will line up first on Sunday.
After recently admitting he was struggling in mixed-weather conditions, particularly with finding grip on slicks on a damp circuit, Leclerc thought his performance in Q3 was a reward for his efforts to cure that weakness.
"Not bad qualifying for us, especially in those conditions," Leclerc said.
"It is always tricky to put everything together. I put a lot of work in those conditions, as I wasn't really comfortable a few races ago. And it seems to pay off.
"We went a bit too early for that last run, but pole was definitely not for us today.
"Max was too quick, but we could have been a bit closer. Having said that we have a great starting position for Sunday."
Leclerc was hindered on his first Q2 flyer by Haas driver Kevin Magnussen, who stuck to the racing line after hitting the wall and damaging his car, for which the Dane was summoned by the FIA stewards.
"It was really tricky. I had Kevin also that went in the wall and then continued in front of me," Leclerc added.
"So I didn't put a lap in early and then you've got all the pressure on that last lap that, and in those conditions it wasn't easy.
"But at the end, everything went well. So yeah, happy.
"Having said that, there's still quite a bit of work to do in order to catch the Red Bulls."