When she took to her runway surrounding her in-the-round stage set up in the middle of the stadium, helpers were on hand to squigee water from her path.
It was the final show of her world tour to promote her latest album 25, and Adele's promoter Michael Coppel had already warned fans this might be her only tour down under.
Last week, he told the Daily Telegraph: "We may never see her again."
The singer confirmed at the end of last night's show that touring wasn't for her and she may never venture out on the road again.
"Touring isn't something I'm good at ... applause makes me feel a bit vulnerable. I don't know if I will ever tour again. The only reason I've toured is you. I'm not sure if touring is my bag," she told the 40,000-plus crowd.
Adele called her tour "my greatest accomplishment in my career" and burst into tears while telling the crowd the reason she'd done it was because of their support.
She also admitted she'd wanted to do it to see why other major artists spent months on the road. "It's changed my life. I understand why I do it," she said.
Adele's New Zealand shows broke records for ticket sales. No other artist has sold out Mt Smart Stadium three times.
How the show unfolded:
9.57pm: Adele's show has come to an end with a stunning finale of Someone Like You. Drenched punters dodged puddles as they left the stadium, but many had big smiles on their faces.
9:43pm: Adele says this is the only show on the tour it has rained at. "It's changed my life, I understand why I do it." She's broke down in tears while thanking the crowd before Someone Like You starts.
9:42pm: Giant puddles are forming around Mt Smart Stadium as Adele's final show comes to a close. She's spent time thanking her band for her 15 month tour. "Touring isn't something I'm good at - applause makes me feel a bit vulnerable. I don't know if I will ever tour again. The only reason I've toured is you. I'm not sure if touring is my bag. My greatest accomplishment in my career is this tour."
9:35pm: She's crying during When We Were Young."You have to sing it for me" Adele tells the fans.
9:17pm: The rain is causing havoc with technology. One of the main video screens is faulting. Confetti is stuck to everyone.
9:04pm: Adele is now putting on someone's spare poncho. It's pink!
9:02pm: She's shooting the T-shirt canon even in the pouring rain. "I'm gonna get my gun out ... she shoots she scores". Now the mic is cutting out.
Adele shooting the T-shirt gun in the rain.
8:48pm: Adele admitted that the weather was making "the glue from my eyelashes ... leak into my eyes and make everything blurry".
8:44pm: Rain continued to pelt Mt Smart Stadium as Adele delivered a note perfect version of Skyfall, her James Bond theme song complete with an all-male choir. She also told the full story of how she ended up writing the song, and asked for everyone to cheer for an "all-female" Bond.
8:34pm: She's drying her hair with a towel and says she keeps swallowing mouthfuls of water.
8:33pm: The TVs in the inner circle have cut out from the rain and Adele is asking the crew to fix them so she can play her James Bond theme song.
8:25pm: There's a lot less chat than previous shows. You get the sense she doesn't want to keep people standing in the rain longer than they need to.
8:24pm: She's spending just as much time in the rain as she did out in the open at other shows. There isn't an ounce of diva in her.
8:13pm: Adele has addressed the rain hammering her final Auckland show. "You poor things," she said. "It's really raining isn't it?" She also expressed concern about the weather affecting her stage setup. "Who wants to make a bet with me I'll fall over at some stage ... or get electrocuted by my microphone."
Adele getting soaked but loving it as she entertains a packed Mt Smart Stadium.
8:12pm: "I just spent two hours in hair and makeup for nothing".
8:10pm: She soon got amongst it, venturing onto the stage's circular platform as helpers squigeed the walkway for her.
8:08pm: Adele has kicked off her Auckland show by laughing in the face of a torrential downpour. The UK singer emerged onstage for her third and final Auckland show singing the opening bars of Hello, cracking up between lines as rain swirled over her.
8:00pm: The rain is torrential and Adele is getting soaked but laughing about it.
7:52pm: Concertgoers at tonight's Adele show will be kicking themselves if they haven't brought ponchos, as heavy rain has started to fall over Mt Smart Stadium.
7:50pm: The final official show of Adele's world tour is underway in Auckland.
Upward of 40,000 are packing into Mt Smart Stadium for the pop star's final New Zealand show before she heads home to London after what has been an epic 15-month tour.
With her previous two shows on Thursday and Saturday, Adele has captured the hearts of thousands of adoring fans with her impeccable performances and down-to-earth, potty-mouthed banter.
Tonight's weather forecast bears warnings of heavy rain and the possibility of thunderstorms, but fans remain undeterred.
Adele - as well as performing a plethora of hits including Hello, When We Were Young, Rolling In The Deep and Someone Like You - has consistently made headlines with her on-stage antics here in New Zealand and it's added to the excitement.
Thursday saw her flailing after her stage was crashed by two beetles, until she eventually pulled up a young Kiwi fan to help rid her of her pests.
Saturday's show saw her brought to tears by a rousing kapa haka performance, including our world famous haka.
And amidst all the hidden letters, fireworks, T-shirt canons and of course, the music, tonight's show is sure to even more surprises on tour as the singer bids farewell to New Zealand.
