Extreme precipitation related to circulation types for four case studies over the Eastern Mediterranean

Abstract

The analysis of the links between the extreme precipitation and the associated atmospheric conditions through an aloft circulation type approach at the 500-hPa geopotential level, for the time period of 1958–2000, is the main motivation for the present study. Four stations in the eastern Mediterranean (17.5° E to 37.5° E and 30° N to 40° N) were selected as separate case studies. The extreme precipitation conditions were defined by the two most widely used indices: the 90th and 95th percentiles. It was found that two cyclonic types (C – with its centre over the station and Cwsw – with its centre at the WSW of the station) were mainly associated with extreme rainfall conditions for all the selected stations. Generally, these circulation types are deepening during days with extreme precipitation in comparison to the general mean field of the type.