St. Louis, Missouri – A rare Midwest earthquake early Tuesday is raising awareness across Missouri as a surge of Arctic air sends temperatures sharply lower, creating conditions that could trigger frost quakes during the coldest overnight hours.
According to the U.S. Geological Survey, a 3.5 magnitude earthquake struck central Illinois shortly before 2 a.m. Tuesday, centered about 35 miles south of Springfield. The shallow quake was felt across much of Illinois, with thousands reporting shaking and loud rumbles before sunrise. Given Missouri’s proximity to the New Madrid Seismic Zone, seismic events in neighboring states often draw close attention, even when no damage is reported.
As the deep freeze spreads across Missouri, geologists say rapid temperature drops can lead to frost quakes, also known as cryoseisms. These occur when moisture in the ground freezes suddenly, causing soil and rock to contract and fracture. The result can be a loud boom or brief shaking that may rattle homes, garages, and vehicles, often overnight or before dawn.
Central and northern Missouri, including St. Louis, Columbia, Jefferson City, Kansas City, and areas along the Mississippi and Missouri rivers, may be more susceptible as temperatures plunge following recent rain or wet ground conditions. Frost quakes are shallow and localized but can crack pavement, foundations, and underground utilities.
State emergency officials emphasize that frost quakes are not tied to fault lines and do not signal larger earthquakes. Residents are encouraged to remain alert during the coldest hours, inspect property if shaking is felt, and report loud booms or ground movement to local authorities or the USGS. With dangerous cold expected to persist through midweek, additional advisories or alerts may be issued as conditions continue to evolve.
