Tomato is a thermophilic species, therefore success in field crop cultivation depends on the course of temperature and precipitation during growing season. The aim of the study was to analyse tomato water needs covering during the May-August period with regard to the course of pluvio-thermal conditions in the area situated to the south of the Krakowsko-Częstochowska Upland in the years 1971-2013. On the basis of temperature from the meteorological station Kraków-Balice in the years 1971-2013, a clear increase in air temperature in the months from April to August was noted, that amounted to approximately 0.3 to 0.4^oC per decade. As a result of air temperature increase, the evapotranspiration rises, which causes higher tomato water needs. It was found that the frequency of precipitation excesses and deficiencies exceeding the value of one standard deviation s, i.e. the occurrence of years too wet and too dry for tomato, has significantly increased since 1991. The highest incidence of excessive precipitation was characteristic of May, June and August. In the consecutive decades of the period of 1971-2013 excessive precipitation was observed in from 2 to 9% of cases in May and from 2 to 7% of cases in June and July. Since the 90s, in June and July an increase of the deficiencies is observed, and in the last period (2001-2013) the frequency of excesses and deficiencies  was observed in every month of examined years.