Bad weather: unsettled conditions return – heavy thunderstorms in the north
On Sunday, the storm front will move away from Italia. The resulting shift in air currents will push warm air towards the central and southern regions, particularly towards Sicily and Puglia
Key points
An Atlantic air mass is set to sweep across Italia between Thursday and Saturday, bringing intense, localised thunderstorms and widespread rain. This is indicated by the analysis carried out by meteorologists at TempoItalia.it using the Icon model from the German meteorological service DWD, according to which the Atlantic air will come into contact with masses of air laden with moisture and energy that have built up over the past few days, generating short but violent downpours.
Thursday in the North
The weather system is expected to begin overnight or in the early hours of Thursday 21 August, with the first thunderstorms over the Western Alps, Upper Piedmont, the Lombardy Pre-Alps and South Tyrol. Western Liguria and the hinterland are also expected to be affected at this stage. As the day progresses, the unsettled weather will spread to the plains of Piedmont and Lombardy, as well as to Liguria, with spurs extending towards Corsica and western Sardinia. By the evening, it will also affect the Triveneto region and Friuli-Venezia Giulia.
On Friday, the journey down to Tuscany
Friday 22nd is the day on which the model places the greatest emphasis: the band of weather systems will stretch from the Western Alps to Friuli-Venezia Giulia, affecting Piedmont, Lombardy, Veneto, western Emilia-Romagna and Liguria. The key development will be the southwards spread of the system, with the unstable weather reaching northern Tuscany, the Tuscan-Emilian Apennines and the Tyrrhenian Sea as far as Sardinia and Corsica. In this area, self-sustaining thunderstorms may develop – a phenomenon in which new storm cells form repeatedly over the same area, fuelled by the same incoming airflow, with rain persisting for hours over a confined area.
Campania and Basilicata are also affected
On Saturday, the weather system will shift towards the Adriatic coast: Friuli Venezia Giulia, Veneto and Emilia-Romagna, then Marche, Abruzzo and Molise, with the central Apennines acting as the main catalyst. The inland areas of Campania and Basilicata will also be affected, whilst further south, convective cells will form between the Tyrrhenian coast of Calabria and north-eastern Sicily.
Among the consequences, hailstorms – even of moderate intensity – may occur, whilst the development of thunderstorms cannot be ruled out in some areas. Complicating matters is the fact that the ground has been dry for months; it absorbs water less effectively than damp soil and encourages surface runoff: there is a risk of sudden flooding even in places where, under normal circumstances, the rain would not have caused any problems.
