Overview
- The magnitude 7.4 earthquake that struck near Ciudad Hidalgo on July 17, 2026 has produced about 2,609 aftershocks, the Servicio Sismológico Nacional reported with the largest secondary reaching magnitude 6.5.
- Dozens of low‑magnitude events were logged on September 16–17, 2026, including M3.7 near Huixtla and Pijijiapan, M3.8 off Pijijiapan, and M3.9 off Mapastepec, and officials reported no significant material damage or casualties.
- Protección Civil and the SSN maintain constant monitoring and public advisories, urging inspections of gas and electrical installations and keeping emergency kits ready for communities in Chiapas.
- The federal government will run the Segundo Simulacro Nacional at 12:00 pm on September 19, activating seismic alerts on more than 80 million cellphones and using thousands of loudspeakers to test response systems.
- Chiapas’s high hazard stems from the Cocos plate subducting under the North American plate, a process that commonly generates long aftershock sequences and leaves the region liable to strong secondary shocks weeks after a major quake.