Overview

• SSN logged three pre-dawn quakes on Sept. 3 measuring 4.0–4.2 near La Choapas, Veracruz; offshore Pinotepa Nacional, Oaxaca; and south of Mapastepec, Chiapas.
• Early Sept. 2 brought three additional events of 4.0–4.3 with epicenters near Vicente Guerrero (BC), Mapastepec (Chiapas) and Ometepec/Metepec (Guerrero), none meeting alert criteria.
• A stronger Sept. 1 quake off San José del Cabo was estimated at 4.8 and was followed by a 3.8 at 22:59 and dozens of small replicas, with local reports of damage and emergency response.
• SASMEX reiterates numeric activation rules that factor epicentral distance, noting quakes below roughly magnitude 5–6 do not trigger citywide sirens.
• SSN’s August report counted 3,081 events nationwide, including a M6.0 off Chiapas on Aug. 9, as UNAM urges preparedness and rejects date-based earthquake myths.