Doors rattled. Houses shook. One Facebook poster said, “it felt like the floor lifted up underneath us.”

Sorry folks. There was no earthquake in Baldwin County last week.

Social media accounts lit up at 10:47 on Thursday, Feb. 10 after residents in central and south Baldwin reported the ground shaking beneath them.

Officials at the National Weather Service in Mobile said an earthquake would be rare in the state and no seismic activity was recorded last week.

Instead, officials say the disturbance was likely caused by the military.

Michael Mugrage, a meteorologist with the National Weather Service, said sonic booms caused by military exercises being held in the Gulf are frequently reported. When atmospheric conditions are right, those booms can travel farther and be felt more strongly.

Thursday was the right day for that to happen.

Temperatures on the surface were lower than those in the upper atmosphere, a condition called temperature inversion.

Sound travels easier where the temperature is warmer. Meaning that boom became trapped in a warm layer of air above the Earth. The warm air moved carrying the boom with it into central Baldwin.

And then boom. Literally. Houses shook.

“You often have that kind of atmospheric conditions overnight or in the morning hours, Mugrage said. “That’s why a thunderstorm at night sounds a lot more ferocious than in the day. That inversion level is usually present and the sound of the thunder carries a lot easier.”

However earthquakes, are not completely unheard of in the state.

Alabama has exerpienced roughly 20 earthquakes since the beginning of the 20th century, none reaching above magnitude 5.1. The most recent was Dec. 22, 2021 when a quake measuring 3.1 magnitude struck just southwest of Maplesville in Chilton County, shortly after midnight.