The ash cloud from a Chilean volcano is causing more widespread disruption to flights.
A sudden wind change moved the ash cloud back over New Zealand at an altitude of between 20,000 and 40,000 feet.
Jetstar and Qantas grounded flights in and out of Christchurch and Queenstown on Wednesday.
Both airlines have cancelled all their flights to and from Wellington, Queenstown and Christchurch, on Thursday morning.
Air New Zealand is continuing to fly.
The ash cloud has already caused thousands of flight cancellations since it first arrived in New Zealand two weeks ago.
Qantas says it has cleared last week's backlog of passengers by adding two extra services between Auckland and Sydney.