The center areas surrounding the Tyrrhenian Sea are categorized as hot-spots for severe occurrences, but not alone. According to a research by the CNR, the amplification of these occurrences is also conditioned by the continuing climate change.
Recent research has shown that tornadoes are not uncommon occurrences in the Mediterranean region, and in particular, in the country of Italy. Atmospheric Research is the journal that published the findings of a study that was carried out by the Institute of Atmospheric Sciences and Climate of the National Research Council (Cnr-Isac). This study confirmed the existence of certain regions that are most susceptible to high-intensity tornadoes. One of them is represented by the center regions that border the Tyrrhenian Sea (Lazio in particular); other locations in Italy that are severely impacted include the south-eastern regions (Puglia-Calabria), as was previously emphasized in earlier studies by the same authors; and the Po Valley.
According to Elenio Avolio of Cnr-Isac, "the intensification of these phenomena, over the years, is also conditioned by the ongoing climate change." It has been confirmed that there are specific forcings, such as the surface temperature of the sea, that play an important role in the development of such events. "In the region of the Mediterranean, the territories of central Italy and the Tyrrhenian Sea might be thought of as a "hot point" for tornadoes. In this respect - says Avolio - 32 years of data (1990-2021) were evaluated, isolating a substantial number of tornado occurrences such as high intensity and low frequency (445 across Italy). In order to find the predominate atmospheric conditions that were related with the reported tornadoes, statistical analyses were carried out by examining both data (radio soundings) and outputs from large-scale models (re-analysis). Therefore, it was conceivable to establish certain predominating atmospheric configurations that had the potential to be conducive to their growth in the region that was the subject of the research ".
In terms of the Tyrrhenian Sea, the average atmospheric conditions are characterized by a region of low pressure over northwestern Italy, both at altitude and on the surface, as well as by south-western ground winds that are capable of transporting air that is warmer than average towards the regions that are being affected. The application of high-resolution weather forecasting models has, over the course of many years, made it possible to achieve significant levels of knowledge on the dynamics of these events, which, by definition, are highly localized in time and space and, as a result, are exceptionally challenging to predict. A tornado that struck the coast of Lazio on July 28, 2019, and is regrettably recognized for being the cause of death for at least one person.
"The results showed how it is possible to successfully predict high values of specific indicators of atmospheric instability and deep convection typical of tornadoes, as well as to correctly simulate the structure of the convective cells responsible for the genesis of such events - comments Avolio - the result poses the emphasis on the importance of an integrated modeling / observational meteorological system dedicated to the monitoring and operational forecasting of such intense phenomena ".