The Federal Aviation Administration is investigating why a Southwest Airlines flight veered off course and had a frighteningly close call last month with LaGuardia Airport’s air traffic control tower.

Southwest Flight 147 from Nashville to New York City flew off course because of bad weather as it approached for landing around 1 pm on March 23, the agency said.

After circling the busy airport once, the plane flew as low as 300 feet, prompting an audibly alarmed air traffic controller to urge the pilots: “Go around! Go around,” according to audio captured by LiveATC.net.

The crew was then instructed to abort the landing and climb to 2,000 feet – with the controller saying the plane was not lined up with the runway.

“He was not going to land on the runway,” the controller said, after telling the pilot to “continue climbing.”

The flight with 150 passengers and crew on board ended up being diverted to Baltimore and landing safely there, “after encountering turbulence and low visibility at New York LaGuardia Airport,” Southwest said.

“We are reviewing the event as part of our safety systems,” an airline spokesperson said.

The National Transportation Safety Board said it was also looking into the incident but did not plan to issue any immediate reports.