NASA postponed the scheduled launch of its super pressure balloon (SPB) from Wanaka, New Zealand, at 2 a.m. Saturday, April 8 (New Zealand time) due to unacceptable stratospheric weather conditions for operations.
Along with monitoring ground and lower-level winds (up to 300 meters) on launch day, stratospheric wind conditions at 33.5 km (110,000 feet), which is where the balloon will float, also need to be set-up favorably to support a launch attempt.
While ground and lower-level winds were conducive for launch, winds in the stratosphere were not. A counter-clockwise flowing eddy has developed to the west of New Zealand’s North Island. Forecast models had the balloon launching from Wanaka and then traveling north bisecting the South Island before eventually getting caught up in the light and variable winds of the eddy. Ideally, an eastward trajectory after lift-off is preferred, though not necessarily required.
“Had the forecast stratospheric models pushed the balloon further west—not unlike what we saw in our 2016 launch—we would have seriously considered moving forward with our launch attempt,” said Gabe Garde, NASA’s mission manager for the balloon launch. “Unfortunately, there’s too much uncertainty in the final trajectory forecast given the nearby eddy pattern in the stratosphere. More opportunities will present themselves as we continue to move forward in the campaign.”
NASA will announce by 2 p.m. Saturday, April 8, whether or not Sunday’s weather will support a launch attempt.