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The Mediterranean is a 'hot spot' for the genesis of different types of severe weather events, including potentially damaging wind phenomena like downbursts, whose occurrence and evolution in this geographical region have not been documented in the literature. This paper is part of an interdisciplinary collaboration between atmospheric scientists and wind engineers with the objective of conducting a comprehensive analysis of the field measurements and weather scenarios related to nonsynoptic wind systems in this area. The downburst that struck the Livorno coast of Italy at about 1310 local time 1 October 2012 is investigated as a relevant test case for such severe wind events. The wind velocity records detected by ultrasonic anemometers, part of a monitoring network created for the European 'Wind and Ports' and 'Wind, Ports and Sea' projects, are analyzed and decomposed in order to inspect the main statistical features of this transient event. The analysis of the meteorological precursors to this event is carried out making use of model analyses, standard in situ measurements, remote sensing techniques, proxy data, and direct observations. The results obtained bring new insights into a downburst's onset and detection in the Mediterranean, its evolution at the local scale, and possible connections to specific synoptic-scale weather conditions like secondary cyclogenesis in the lee of the Alps. [ABSTRACT FROM AUTHOR]

Downbursts are intense thunderstorm winds that can be found in most, if not all, regions around the globe. An accurate experimental investigation of downburst winds requires the proper geometric and kinematic scaling between the model downburst (m) created in a wind simulator and the full scale downburst event (p). This study makes a threefold contribution to further understanding of downburst outflows. First, the article introduces a new scaling methodology for downburst outflows based on the signal decomposition techniques of p and m downburst wind records. Second, the study describes a large set of m downbursts produced in the WindEEE Dome simulator at Western University and critically discusses their similarity with a large set of p events detected in the Mediterranean. Third, using the proposed scaling methodology, this paper attempts to partially reconstruct two p downburst events recorded in Genoa and Livorno, Italy. In total, 17 p and 1400 m downburst outflows are investigated herein, which represents the largest database of p and m downbursts combined. The similarity between p and m downbursts is quantitatively demonstrated for both mean and fluctuating components of the flows. The scaling method is verified by accurately predicting the known anemometer height of p events using m downburst measurements. Image 1 • Novel methodology for downburst scaling in wind simulators developed. • 1400 and 17 physically simulated and full scale events, respectively, analyzed. • Transient and turbulent features of physically simulated downbursts investigated. • Two downbursts in the Mediterranean reconstructed from simulations in WindEEE Dome. [ABSTRACT FROM AUTHOR]