Niedobór i rozkład opadów w Siedlcach w latach 1971-2005

Meteorological data from 1971–2005 from a meteorological station situated in Siedlce coma from the Institute of Meteorology and Water Management (IMGW). In the present paper, the number of days with recorded precipitation was determined applying the criterion of Olechowicz-Bobrowska. In order to examine moisture excess and shortage a (P-ETR) index (climatic water balance) was calculated. Dry and wet months were determined following the Kaczorowska method. Sequences of days without rain were determined on the basis of Koźmiński criterion (1986). An average number of days with recorded precipitation (≥ 0.1 mm) during the growing season amounted to 83 days. The periods without rain over the growing seasons most and least frequently occurred in April, August and October, and in June respectively. The highest water shortages in the analysed multi-year period were recorded in May and August. The positive balance between precipitation and evaporation was observed only in the autumn months (September, October).