The paper presents selected characteristics of atmospheric precipitation in the Iława and Dobrzyńsko-Chełmińskie Lake Districts determined on the basis of data from four stations of IMGW (Institute of Mete-orology and Water Management) – Prabuty, Biskupiec on Osa, Brodnica and Lubawa. The study covered a period of 50 years (1951-2000). The analyses were made with the use of a 30-year moving sample. Critical values of monthly and seasonal sums of precipitations for various levels of probability were calculated from the gamma distribution, and then their trends were determined. Also, probability of occurrence of precipitation anomalies was calculated. The probability of occurrence of precipitations below the lower limit of the norm at all the stations displayed a significant increasing trend in August and in July, however the probability of occurrence of precipitations exceeding the upper limit of the norm generally displayed signifi-cant decreasing trends at all stations in July and August, in the summer season and in the year period.