Weather warning: the formation of fearsome superstorm thunderstorms is expected in some of our regions in the next few hours: these are extreme phenomenacapable of triggering heavy rainfall, very strong winds, hailstorms and flooding.
All eyes on the next few hours when in the course of Wednesday 12 June a new phase of intense bad weather is expected in particular on Piedmont, Lombardy, Emilia Romagna and Veneto where very intense thunderstorms are expected with a serious risk of storms and local flooding. These areas will be found in some sort of convergence zone where different air masses interact: on the one hand the warm and very humid currents of Sirocco and on the other the irruption of more unstable air at high altitude driven by the cyclone centered between the Scandinavian Peninsula and the British Isles. The potential energy involved (CAPE in technical terms) will be very high also due to the still present humid heat transported by the African anticyclone.
According to the latest updates the areas most at risk they will first be the Piedmont (province of Cuneo and Turin) and subsequently the Lombardy. In the evening a thunderstorm line will form with a serious risk of medium-sized hail and strong gusts of wind in the provinces of Milan, Monza-Brianza, Como, Lecco and Bergamo.
Maximum attention between evening and night Emilia Romagna and lower Veneto where due to the convergence between Bora and Scirocco winds we do not exclude the training of a supercell especially between the provinces of Ferrara/Ravenna and Rovigo. Therefore pay maximum attention!
The SUPERCELLS
In the classification of thunderstorms, the supercells they are the phenomena more dangerous in terms of power released and potential damage. It’s about immense storm systems high up to 10/12 km within which there is a low pressure area defined in the technical term mesocyclone.
With the increasing heat, so does thepotential energy (humidity and heat in the lower layers of the atmosphere) at play for the development of impressive storm cells, capable of causing extreme weather events like that of large hail and, in the rarest cases, even gods tornado (or whirlwinds, remember that the two terms are synonymous).
BIG HAIL and DOWNBURST
Not only. With supercells it also increases the chances of large hail (until 8-10cm in diameter) associated with strong gusts of wind up to 120-130 km/h, slang calls downburst. The latter, also defined as descending gustis a meteorological phenomenon that consists of strong downward gusts of wind with horizontal motion exiting the advancing front of the storm. The gusts can reach very high speeds, even above 100 km/h.
CIVIL PROTECTION ALERT
Based on available forecasts, the Department of Civil Protection in agreement with the regions involved, who are responsible for activating civil protection systems in the territories concerned, issued a warning of adverse weather conditions. The weather phenomena, impacting on the different areas of the country, could determine hydrogeological and hydraulic criticalities which are reported, in a national summary, in the national criticality and alert bulletin which can be consulted on the Department website (http://www.protezionecivile.gov .it/).
On the basis of the foreseen and ongoing phenomena, it was evaluated for the day of Thursday 13 June, orange alert on part of Lombardy, yellow alert on the remaining sectors of Lombardy, part of Piedmont, Friuli Venezia Giulia, a large part of Veneto, Emilia-Romagna and parts of Tuscany, Marche and Abruzzo.
