My mom and dad both heard a loud intense scream in the middle of the night. What does this mean?

My mom described the scream as loud and intense, she said it was like someone was screaming right into her hear. My dad heard the same scream on the same night, but at the time he was several states away. They were both in deep sleep so the scream was loud enough to wake them. I believe this is a premonition or a warning of something bad. I've tried to do some research on premonitions online but haven't had much luck. Does anyone know what this could possibly mean, or have any suggestions on where I could find some information?