Denver, Colorado — Loud booming noises reported overnight across parts of the Rocky Mountain region are raising questions from residents, particularly in communities spanning Colorado and Wyoming near the Interstate 25 corridor, where sudden rumbles were heard during the coldest nighttime hours.
According to the National Weather Service, the sounds are consistent with cryoseisms, commonly known as frost quakes. These events occur when water-saturated ground freezes rapidly, causing underground expansion that cracks soil or rock and produces a sharp, explosive noise.
Meteorologists said recent weather conditions created a favorable setup across the Rockies. Snowmelt, rain, and mixed winter precipitation earlier in the period saturated the ground. Temperatures then dropped quickly from above freezing to well below zero over a 36- to 48-hour window, increasing pressure beneath the surface.
The National Weather Service emphasized that frost quakes are not earthquakes and do not indicate seismic activity. While the noises can be loud enough to shake homes or wake residents from sleep, the events are typically brief and rarely cause damage.
Reports shared with forecasters described booms heard late at night into early morning hours, including residential areas near major travel routes such as Interstate 25, which runs north to south through the Front Range and into southern Wyoming, where some of the coldest overnight temperatures were recorded. No structural damage or roadway damage related to frost quakes has been reported.
For commuters and overnight drivers, officials said there are no closures or pavement impacts tied to the phenomenon. However, continued freezing temperatures may still create common winter travel hazards, including icy bridges, mountain passes, and shaded stretches along Interstate 25 and nearby highways.
Meteorologists note frost quakes are most likely when rapid temperature drops follow wet ground conditions. Isolated events may continue until temperatures stabilize or soils fully freeze.
Residents are encouraged to remain weather-aware but reassured that the sounds, while unusual, are a known cold-weather occurrence.
