Data on rainfall, water surface temperature and salinity from the Bay of Santa Marta, Colombian Caribbean, are presented for the period November 1978 tó May 1982. Including data already published (Müller, 1979) generalizations of the anual patterns are obtained. Additional measurements of the variation of water temperature and salinity in the course of one day, preliminary values of light quanta, together with available data on oxygen content and saturation, pH, alcalinity, stability, wind direction and velocity, hours of sunshine, air temperature, and water discharge of the river Manzanares permitted a quantitative characterization of the dry and rainy season which can be observed in the area of investigation.