AN OVERVIEW OF A HEAVY RAIN EVENT IN SOUTHEASTERN IBERIA - THE ROLE OF LARGE-SCALE METEOROLOGICAL CONDITIONS

The heavy rain event of 30 January to 4 February 1993 in the Segura Ba sin in SE Iberia is investigated. The study emphasizes the atmospheric processes that led to thunderstorm development. The meteorological sc enario has been separated into preconvective and convective periods an d into large-scale and subsynoptic settings. The warm, moist air flow from the Mediterranean Sea, channelled by a high-over-low blocking pat tern with a cold front over southeastern Iberia appears to be the main reason that helped trigger a severe weather occurrence. The study of the mesoscale environment parameters showed an enhanced conditional un stability through a deep troposphere layer with a moderate to strong v ertical wind shear that promoted conditions to allow organization of l ong-lived convective structures.