NASA has called off the scheduled Tuesday launch of its historic uncrewed mission to the Moon due to a tropical storm that is forecast to strengthen as it approaches Florida.

After two previously canceled launch attempts, NASA is weighing returning the Artemis 1 mission rocket to its assembly site under the threat of extreme weather.

"NASA is forgoing a launch opportunity... and preparing for rollback (from the launchpad), while continuing to watch the weather forecast associated with Tropical Storm Ian," it said on Saturday.

The US National Hurricane Center (NHC) said Ian is due to "rapidly intensify" over the weekend as it moves toward Florida, home to the Kennedy Space Center, from which the rocket is set to launch.

An approaching storm threatens to delay NASA's next launch attempt for its new moon rocket, already grounded for weeks by fuel leaks.

NASA announced Thursday that the cryogenic fueling test this week at Kennedy Space Center did well enough to keep moving toward a launch attempt as early as Tuesday.

"Based on data from the test, teams are fine-tuning procedures for the next launch opportunity, targeted for no earlier than Sept. 27," reads a statement on the NASA website. "The rocket remains in a safe and flight-ready configuration at the launch pad."

The nearly 10-hour test at Launch Pad 39-B on Wednesday saw several issues with liquid hydrogen leaks, some similar to what caused a scrub on the last attempt to launch on Sept. 3.

But mission managers were able to troubleshoot and push through to accomplish all the goals for the test setting the rocket up for what would be its third attempt to get off the ground.