Resumen
Recently developed theory of Lithosphere-Atmosphere-Ionosphere (LAI) coupling pays attention to the processes taking place within the near ground layer of atmosphere. Air ionization produced by radon emanating from the earth?s crust launches the chain of physico-chemical processes which change significantly the composition of air molecules, as well as air temperature and humidity. All these changes, as it was detected earlier, take place one-two weeks before strong earthquakes occur within the area of earthquake preparation. The present paper is an attempt to track these changes using meteorological data collected at meteorological stations close to the epicenters (less than 200 km) of strong earthquakes in México. The atmospheric anomalies were detected both on long term intervals (several tens of years) and within one-two weeks before the earthquakes occur. The long term variations reveal the anomaly for the year of earthquake, while the shortterm anomalies demonstrate the changing dynamics of air temperature and humidity before the earthquake.