This paper presents an analysis of the flash floods that occurred in Catalonia (NE Iberian Peninsula) on 10 June 2000, in the context of the historical floods recorded since the 14th century. The study starts with pluviometric and meteorological analyses (essentially synoptic and thermodynamic) of the episode. There follows a comparison of this event with previous floods for which we have instrumental information, information from archives, or both types of information. In some cases this permitted us to make a meteorological comparison of episodes similar to that of June 2000, and the complete series was used to carry out a frequency analysis of floods that have occurred in the basin under study. The conclusions show that although catastrophic flooding in spring is not as typical a phenomenon as autumn flooding, such floods have been recorded at least once each century, and it can be stated that the synoptic meteorological situation, where recorded, showed similar characteristics in all cases. Copyright © 2003 Royal Meteorological Society

During the period 1996–2000, forty-three heavy rainfall events have been detected in the Internal Basins of Catalonia (Northeastern of Spain). Most of these events caused floods and serious damage. This high number leads to the need for a methodology to classify them, on the basis of their surface rainfall distribution, their internal organization and their physical features. The aim of this paper is to show a methodology to analyze systematically the convective structures responsible of those heavy rainfall events on the basis of the information supplied by the meteorological radar. The proposed methodology is as follows. Firstly, the rainfall intensity and the surface rainfall pattern are analyzed on the basis of the raingauge data. Secondly, the convective structures at the lowest level are identified and characterized by using a 2-D algorithm, and the convective cells are identified by using a 3-D procedure that looks for the reflectivity cores in every radar volume. Thirdly, the convective cells (3-D) are associated with the 2-D structures (convective rainfall areas). This methodology has been applied to the 43 heavy rainfall events using the meteorological radar located near Barcelona and the SAIH automatic raingauge network.

This paper presents an observational study of the tornado outbreak that took place on the 7 September 2005 in the Llobregat delta river, affecting a densely populated and urbanised area and the Barcelona International airport (NE Spain). The site survey confirmed at least five short-lived tornadoes. Four of them were weak (F0, F1) and the other one was significant (F2 on the Fujita scale). They started mostly as waterspouts and moved later inland causing extensive damage estimated in 9 million Euros, three injured people but fortunately no fatalities. Large scale forcing was provided by upper level diffluence and low level warm air advection. Satellite and weather radar images revealed the development of the cells that spawned the waterspouts along a mesoscale convergence line in a highly sheared and relatively low buoyant environment. Further analysis indicated characteristics that could be attributed indistinctively to non-supercell or to mini-supercell thunderstorms.