Abstract
The aim of this study was statistical description of the rainfall changes in the vicinity
of Szczecin in the years 1991–2000 and approximation of daily rainfall using the harmonic and
polynomial functions. On the basis of original data, mean values of monthly rainfall and their
standard deviations were shown. Mean annual rainfall amounts (total precipitation) in the
studied decade (10 years) equaled 575 mm. The highest mean monthly rainfall was in July
(76.3 mm), and the smallest – in October (32.7 mm). From both the mathematical models of
daily rainfall as a function of day number of year more adequate was four-order polynomial
(determination coefficient R2
= 0.822). There has been attempt to model the distribution of the
rainy days number in selected 30-day month using the theoretical binomial distribution.