An analysis of short duration high-intensity rainfall events in Cracow area

The study involves a preliminary analysis of short-duration high-intensity rainfall events in the area of Cracow. The events were selected from a 2-year data record from the MPWiK (Miejskie Przedsiębiorstwo Wodociągów i Kanalizacji [Municipal Water and Sewage Company]) in Cracow. A spatial analysis was carried out by comparing rainfall events with highest single totals which occurred at the same time at all observed precipitation stations. Extracted were nine cases from the data record of 2013 and ten from the data record of 2014. Each of the analysed events was classified according to the Chomicz scale for rainfall intensity in order to distinguish maximum rainfalls, in particular of the following types: heavy rainfalls, rainstorms and torrential rains. Additionally, observed were cases of the most unfavourable rainfall events, i.e. ones with the highest totals in the observed year. In both 2013 and 2014, certain areas in Cracow were observed to be characterised by a pattern of repeating rainfall types. Also, a change in the rainfall category was observed from lower into higher and reverse in certain areas represented by the same gauging stations. At the stations located in varying distances within one urban area of Cracow, the intensity of rainfall varied from rainstorm A1 to torrential rain B1.