An analysis of diurnal variations of heavy hourly precipitation in Krakَw using a classification of circulation types over southern Poland

The paper presents parameters of the diurnal rainfall cycle for rainfall equal or exceeding 2.5 mm h−1 during both the summer and winter halves of the year. It then discusses the impact of various circulation systems on the distribution of the frequency of rainfall occurrence during a 24-h day in the summer half of the year. The results of these investigations contribute to a greater understanding of the atmospheric processes associated with heavy precipitation and may be used to improve the forecasting of the temporal distribution of short-duration convective precipitation. ern with a single heavy rainfall maximum was identified. A variety of diurnal patterns of amplitude and time of maximum rainfall emerged depending on the atmospheric circulation determining the thermal and humidity properties of air masses. The paper was based on hourly rainfall records in Kraków and on a daily catalogue of atmospheric circulation types in southern Poland spanning the period 1886–2007.