Joe Jonas Paddleboards With Rumored Girlfriend Stormi Bree In Australia

Joe Jonas has moved on from Sophie Turner ... hopping on a yacht with Stormi Bree, and yeah -- they 100% look like a couple now, in case it wasn't already obvious.

The JoBro singer enjoyed a day on the water in Sydney Harbour -- yes, he's in Australia right now with his brothers -- with the model/ex-Miss Teen USA winner ... swimming, stand-up paddleboarding and even enjoying a few beverages onboard.

Joe and Stormi have been spending a bunch of time together ever since he and Sophie divorced. It's easy to see why Joe's into Stormi ... just check out her bikini bod -- it's rockin'!.

While Joe and Stormi enjoyed some quality time together on their paddleboard, this was actually a group outing. Also onboard the yacht ... Nick Jonas and a few other party people.

Stormi's body isn't the only thing that's smoking, BTW... Joe's also lighting one up, puffing away on the deck.

Joe and Stormi got the full Sydney experience -- the yacht took them past two famous landmarks ... the Sydney Harbour Bridge and the Sydney Opera House, which they documented on social media.

The rumored couple -- who, frankly, are probably/most definitely dating -- is Down Under as the Jonas Brothers continue on their tour in Australia ... making this their third trip together in as many months.

We've previously seen Joe and Sophie hanging out in Los Cabos and going skiing in Aspen. They've also been spotted hobnobbing in other cities -- they're hanging out a ton these days.

Remember ... Joe and Sophie are sharing custody of their kids, and we usually see Joe with Stormi when it's Sophie's turn to parent. Of course, they're in the middle of a divorce too.

Speaking of Sophie ... she's moved on herself, coupling up with British aristocrat Peregrine Pearson.