The launch of a huge super-pressure balloon by NASA in Wanaka has been delayed again, casting its future into doubt.
The balloon, which is 70m high with a diameter of more than 100m, was due to be launched today, but NASA said El Niño conditions were causing unacceptable weather conditions.
Having waited more than a month, NASA said it would monitor the weather until at least the end of May.
For now, it was trying to arrange a new launch date and would make an announcement on Monday.
It said Wanaka should be a place with good weather conditions, but it was not unusual to hit a bad patch.
"Wanaka typically offers a very high probability for weather conditions conducive for launching NASA's scientific balloons," the agency said in a statement.
"Still, it is not uncommon for any of NASA's worldwide launch sites to hit a patch of bad weather that results in postponed launch attempts."
Metservice said Wanaka had experienced high winds over the past few weeks which would not go away in the next five or six days.
NASA said the weather in the stratosphere had also been unusual for the time of year.
The balloon was set to circumnavigate the globe about the Southern Hemisphere's mid-latitudes once every one to three weeks, depending on winds in the stratosphere.