The ash cloud began drifting into New Zealand's airspace on Saturday night and yesterday Qantas and Jetstar cancelled scheduled transtasman flights to Queenstown. Pacific Blue cancelled its flight from Brisbane to Dunedin.
Outbound flights were also cancelled, causing chaos for more than 400 passengers trying to pass through the two airports yesterday.
The cancellations were among dozens of transtasman and domestic flights axed by the two airlines yesterday, affecting about 1500 passengers. Air New Zealand adjusted flight routes and altitudes to keep flying.
Queenstown Airport Corporation chief executive Steve Sanderson said most passengers unable to fly from the resort to Australia had been flown to Auckland to connect with alternative flights.
The disruption at Queenstown airport had been "pretty minimal" but that could change if cancellations continued for another week or more, he said.
That could see disruption to extra flights catering for the influx of tourists coming for the start of the winter season and the beginning of the Queenstown Winter Festival on June 24.
MetService predictions were for winds to help dissipate the ash over the next few days, but whether that happened was in "the hands of the gods".
"It's a bit like 'is it going to snow tomorrow?"'
International flights to and from Auckland airport were not affected yesterday, but Civil Aviation meteorologist Peter Lechner said the cloud could be over most of the North Island by this morning.
It was difficult to determine how it might affect New Zealand flights, he said.
"The eruption started on the fourth of June and took six or seven days to get to us, so even if the eruption stops now we would still have a further six or seven days of the plume posing a problem for us, possibly.
"We might find that after a few days, the local circulation changes it and takes it all south of us."
The ash cloud was coming from the Puyehue-Cordon Caulle volcano in Chile.
The plume has since drifted at an altitude of between 20,000 feet and 35,000 feet while travelling thousands of kilometres across the South Atlantic, South Africa, Indian Ocean, Tasmania and now New Zealand.
Jetstar yesterday cancelled 10 transtasman flights and 20 domestic New Zealand flights, and Qantas cancelled 22 flights to and from New Zealand and Tasmania.
Pacific Blue's flight from Brisbane to Dunedin was one of three transtasman services provided by the airline cancelled because of the ash cloud, affecting about 200 passengers, airline spokeswoman Melissa Thomson said.
Among those stranded was Dunedin woman Sophie Barker, who was stuck in Brisbane with her two children, but hoping to return home ahead of a crucial neurosurgical appointment later this week. Ms Barker told the Otago Daily Times she hoped to fly to Dunedin on a rescheduled service tomorrow.
She wanted to reach home in time to prepare for a return flight to Sydney on Thursday and an appointment with a specialist neurosurgeon at Macquarie University, in Sydney, the following day.
Ms Barker was battling pressure caused by a cyst, and desperate to make the appointment after two unsuccessful operations in Dunedin.
''You actually can't change anything about it, so you just have to live with it. But I was just like 'Oh God, I don't need this. Not on top of everything else'."
Dunedin International Airport chief executive John McCall said yesterday's disruption was not "out of the ordinary" compared with weather events, but came at a cost in lost income and disruption to passengers.
"It would be a concern if it gets worse, or it's going to carry on for any length of time."
