In this article the authors presented the characteristics of heavy precipitation events which occurred in May and June 2010. During this period of time two significant flood peaks occurred in the upper watershed of the Vistula river. Hourly precipitation sums were registered by automatic channel rain gauges, which have been placed at three different measurement sites situated in separate Krakow districts: Sidzina, Bielany and Skotniki, as well as at two nearby located townships: Gdów and Nowe Brzesko (situated 30–40 km from Kraków). In contrast to most often used characteristics of precipitation (daily sums) the authors employed a unique analysis of separate rain events. In order to compare the results long term precipitation sequences have been used from the Kraków UJ historical weather station. This study confirms that monthly precipitation sums in May 2010 (284.7 mm) have been highest in the observed period of time (1901–2011) and constituted over 400% of the precipitation norm (1971–2000). Precipitation totals in the subsequent weather sites were as follows: 357.6 mm (Sidzina), 232.0 mm (Bielany), 219.6 mm (Skotniki), 404.7 mm (Gdów) and 167.4 mm (Nowe Brzesko). Similar and extremely high precipitation sums have been observed in June 2010 and equaled 170.1, 80.5, 119.5, 221.1 and 170.4 mm respectively. In contrast the historical weather station in Kraków registered 154.3 mm of precipitation which equaled to about 168% of the norm. It should be noted that during May of 2010, 27 days of precipitation have been registered and 15 rainy days were noted in June. Heavy rains, which formed the first flood peak occurred for 6 days in a row (15–20 May). The second flood peak occurred between May 30 and June 4. The total precipitation sum during this particular period equaled 213.7 mm in Sidzina and 207.4 mm in Gdow during the first flood peak and 118.8 mm and 192.3 mm during the second flood peak. It should be pointed out that heavy precipitation during the first flood peak lasted for three consecutive days (May 15–18) with heaviest precipitation falling during the evening hours. The precipitation totals equaled 200.3 mm in Gdow and 200.8 mm in Sidzina. In contrast the second flood peak comprised of five separate rain events.

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