LOUISVILLE, Ky. (WAVE) - If you heard a loud bang or felt a brief shake late Monday night, you weren’t alone. Reports came in from across the region, especially central Kentucky, of sudden booms and vibrations — and the cause may surprise you. The likely explanation: a frost quake. What Is a Frost Quake? A frost quake, also known as a cryoseism, happens when rapidly freezing ground cracks under pressure. After rain or melting snow, moisture seeps into the soil and small fractures in bedrock.