Mesospheric clouds observed in Poland in 1975

Positive observations of mesospheric clouds are tabulated for the period from March to October 1975. Included are data of NLC observations; the altitudes and coordinates of 35 meteorological stations; the time of observation; the elevation of observed noctilucent clouds; limiting azimuths of observed clouds; the morphological forms; brightness of NLC (5-scale classification); twilight tropospheric cloudiness at the time of observation; and general tropospheric cloud cover. The weather conditions during the months of NLC occurrence in Poland (May, June, July, and August) are also tabulated.