Kentucky Frost Quakes Cause Booms in Cold Weather

Residents in Kentucky have reported hearing loud booming sounds and feeling minor vibrations amid a recent stretch of bitterly cold weather, prompting explanations from meteorologists about a natural phenomenon known as frost quakes or cryoseisms.

The National Weather Service office in Louisville received multiple accounts of these unusual noises during the cold snap, which brought temperatures plummeting below freezing. Officials attribute the sounds to water in the soil, saturated from recent rain or melted snow, freezing rapidly as arctic air moves in. This process causes the water to expand by about nine percent as it turns to ice, building intense pressure that cracks the surrounding ground and produces the startling booms, along with subtle shaking.

Evan Webb, a meteorologist with the National Weather Service in Louisville, confirmed the reports and described how the phenomenon unfolds. "I think some people initially wonder if it's an exploding tree or something," Webb said. He noted that frost quakes occur when temperatures drop sharply after periods of above-freezing weather that leave the soil moist, a combination that sets the stage for the rapid freezing.