Earlier investigations (M¿rcz, 1971, 1973) have shown an increase of ionpheric absorption measured at the observatory near Nagycenk, Hungary, after certain geomagnetic storms. As is indicated by the present analyses, extremely high ionospheric night absorption can be enhanced night averages of the potential gradient measured on the ground at the observatories near Nagycenk, Hungary, and Swider, Poland. This enhancement often lasts severak days. A latitude dependence of the effect might be assumed. Different possibilities for the selection of intervals with extraterrestrial influences (on atmospheric electric parameters) have been checked. Results of investigations controlling the meteorological influences are also presented.