Buemi has hence matched Jean-Eric Vergne's series pole record of 15, and his first since the New York City E-Prix in 2019.
The opening sector was incredibly close, with Hughes a nose ahead with a 0.003s advantage. He extended that to 0.05s, but Buemi had been excellent throughout the session in the final sector.
Hughes clocked a 1m09.495s to set the benchmark, but Buemi ended his run to pole with a 1m09.435s to deny Hughes a first Formula E pole.
On the route to the final, Buemi had encountered a seemingly rejuvenated Sam Bird in the semifinal, and the Briton was 0.115s ahead by the close of the first sector.
The Envision driver however turned it around in the second half of the lap and beat the Jaguar driver by less than a tenth.
Buemi had also come from behind to beat Mitch Evans, who had been nearly three-tenths ahead after the opening flurry of corners. Showing resilience and great pace in the final clutch of corners, the Swiss hit back and reversed the arrears to claim a semifinal place for the first time in his Formula E career by 0.249s.
A dramatic semifinal between Hughes and Dan Ticktum was closely fought; Hughes scraped the wall with his front-right wheel in the downhill first sector, giving the NIO 333 driver a 0.2s advantage, which continued to grow.
Although Ticktum looked nearly certain to progress to the duel for pole, a final corner slide handed the spoils to Hughes.
On account of their semi-final times, Bird starts third ahead of Ticktum, who had put Oliver Rowland to the sword with a half-second-plus advantage in their quarterfinal duel, punching in a 1m09.593s to progress.
Hughes' duel against Rowland's Mahindra team-mate Lucas di Grassi was also one-way traffic, and the Briton staked his claim with a 0.3s advantage in the opening sector which gave him a sufficient buffer.
The closest quarterfinal had been Bird's battle with Rene Rast and, although the German's middle sector put them just 0.013s apart in sector two, Bird unlocked a smidgen more pace in the last few turns to stamp his semifinals card.
Rast starts fifth ahead of Evans, while di Grassi and Rowland make it an all-Mahindra fourth row.
The Group A session was red flagged after five minutes of running, as Maserati MSG's Maximilian Gunther put his car into the wall on the exit of Turn 11 after locking up his left-front wheel.
"It was a high speed accident, he's not sure what caused that," said team principal James Rossiter. "We need to analyse the data and see what happened, but just thankful he's okay."
Guenther was later heard on the Formula E broadcast stating that he had to contend with understeer at the front.
His team-mate Edoardo Mortara compounded a miserable day for the Monegasque squad, as his rear stepped out at Turn 16 and he subsequently clouted the wall with his left-rear tyre.
Nick Cassidy had ghosted into the top four at Antonio Felix da Costa's expense, but di Grassi's final lap was enough to put the Kiwi out of progressing to the duels, putting both Mahindras through to the duels. Among the other big scalps of the session, championship leader Jake Dennis also failed to progress.
Neither DS Penske progressed from Group B, as Jean-Eric Vergne could only manage the seventh-best time as Stoffel Vandoorne was ninth-fastest.
Pascal Wehrlein endured a difficult session, having been caught unsighted by Sergio Sette Camara and was baulked at the final corner. This will be investigated by the stewards, and Wehrlein's hopes of a progression to the duels was denied by Evans late on.
In a row consisting of those scorned in the qualifying group stage, Wehrlein starts ninth ahead of Cassidy. Sette Camara provisionally starts 11th, pending the results of the stewards' investigation, next to Dennis in 12th.
Kelvin van der Linde was slowest of the 10 cars able to make it onto the circuit in his first Formula E qualifying session, as Abt team-mate Nico Muller was unable to take part as a consequence of his FP2 crash.