Mild temperatures with snow, rain, freezing rain, and freezing drizzle were followed by Arctic air with VERY strong winds dropping our temperatures quickly today. This has lead to some very loud sounds that some of our viewers have reported late this afternoon and evening. One viewer thought a tree limb had fallen on his house. My mom thought something had been blown into the side of her house, but she didn't see anything.
These are called cryoseismic booms or frost quakes. These only occur in the northern states... those of us who can get pretty cold. Especially when we get cold really fast... and when we have had plenty of moisture beforehand.
When there is a lot of moisture in the soil... and we have a fast drop in temperatures, the water will freeze quickly. Water expands when it freezes and creates a loud pop when it expands fast. It will usually create a crack where it occurs, but your house may be making its own pops from moisture in wood freezing and popping. These rarely cause problems.
Eastern Iowa has had other frost quakes within the past year. Click here to read a story from last February.