An Air New Zealand flight has been turned around after experiencing severe turbulence while trying to land in Dunedin on Wednesday morning.

Meanwhile, a second flight from Auckland to Queenstown had to turn back after it was struck by lightning mid-flight.

Flight NZ681 between Wellington and Dunedin attempted to land twice but then turned back to the capital.

An airport announcement in Dunedin said it was due to severe turbulence and wind shear.

One of the passengers, Megan, told RNZ several people vomited as the flight neared Dunedin.

Passenger Jenny said the crew had been reassuring and everyone had been rebooked on later flights before relanding in Wellington.

She praised the Air New Zealand crew, saying they were professional and personable despite the vomit.

"I remember handing a whole bunch of vomit bags over to the flight crew and I said, 'Oh, what a job' and they go, 'Nah it's all part of it' - like it's not a big deal and that kind of reassurance that you get from your flight crew just really helps."

MetService has a strong wind watch in place for coastal areas of Dunedin and Clutha until 5pm on Wednesday for possible severe southwest gales in exposed places.

Air New Zealand chief operational integrity and safety officer Captain David Morgan said challenging weather across the country was affecting flights.

He confirmed flight NZ681 was unable to land due to strong winds.

"Our customer care and airport teams are working to re-accommodate customers in both Wellington and Dunedin on the next available services," he said.

Air New Zealand said it was the only flight disruption to or from Dunedin.

It said the next flights in and out of Dunedin, shortly after 1pm and 1.30pm respectively, were going ahead as scheduled.

New Plymouth 7-year-old Thijs was on the flight with his mother and said it had been a bit scary. He said if their holiday was delayed they would at least get to see friends in Wellington.

Meanwhile, NZ613 turned back after being struck by lightning on Wednesday morning.

It was undergoing engineering checks, and passengers were transferred to another plane.

"Lightning strikes are not uncommon, and our pilots do train for this scenario," Morgan said.

Main image: (supplied / RNZ)