"The A320 aircraft are undergoing standard engineering checks in Christchurch.
"Lightning strikes are not uncommon. Aircraft are designed with this in mind and our pilots train for this scenario."
One of the passengers on NZ605 said there was a lot of turbulence and the plane quickly gained altitude.
Another passenger on the plane, Ben Taylor, of Wanaka, said: "There was a really loud bang. The whole plane shook and the skies outside the plane were brightly lit up. Afterwards, there was an acrid, burning smell for a few seconds."
Another passenger on the flight from Wellington, Jason Epps-Eades, said the head flight attendant kept spirits up as they "climbed out" and diverted to Christchurch.
"There was a loud sound and a flash of light that went through the plane, then a burnt smell for a few minutes," he said.
Domestic passengers around the country were also experiencing delays after strong winds in Queenstown and Dunedin earlier today.
Three flights from Auckland have been cancelled and four others were facing delays.
An Air New Zealand spokeswoman said they were a flow on effect of the wind conditions.