Overview
- The quake struck at 00:42 local time about 19 km southwest of San Marcos, Guerrero, with SSN reporting magnitude 5.2–5.3 at roughly 10 km depth (lat 16.72, lon -99.55).
- SASMEX sounded public alerts in seven cities—Mexico City, Chilpancingo, Acapulco, Oaxaca, Puebla, Cuernavaca and Toluca—providing 8 to 59 seconds of lead time.
- Mexico City activated emergency protocols, conducted helicopter overflights and infrastructure checks, and reported no affectations; Metro inspections found operations safe.
- SSN indicated the event is a replica of the January 2 magnitude 6.5 Guerrero quake and counted 4,657 aftershocks in the sequence as of 01:30 on January 16.
- The tremor was felt strongly in parts of Guerrero and lightly or imperceptibly in areas of Mexico City and Puebla, where evacuations occurred as a precaution.