Azores high pressure brings sunny start across Italy before mid-week Atlantic storms

Azores anticyclone brings early week stability

Following residual rainfall across eastern Sicily on 13 September, an expansion of the Azores anticyclone is establishing dry and sunny weather across the Italian peninsula. The final showers on Sunday concentrated over the Sicilian provinces of Enna, Caltanissetta, Catania, and the Tyrrhenian coast of Messina before clearing. This high-pressure system is advancing from the Atlantic Ocean toward western Europe and the Mediterranean basin starting Monday, 14 September. Unlike previous heat waves driven by hot African air masses, this maritime anticyclone brings temperate conditions to most Italian regions. Forecaster Mattia Gussoni confirmed that skies will remain clear through Tuesday across northern, central, and southern sectors. Maximum temperatures will range between 29°C and 30°C in central cities such as Florence and Rome.

Atlantic disturbance forecast from mid-week

The period of calm weather will be temporary as an organized disturbance moves toward Italy from northern Europe and the Atlantic on 16 September. Initial precipitation is scheduled to hit the Alps and northern plains on Wednesday before spreading toward the Adriatic coastal sectors on Thursday, 17 September. High levels of convective available energy stored in the lower atmospheric layers could trigger locally intense thunderstorms across northern and central districts. Meteorologist Federico Brescia explained that the incoming weather system will initiate a noticeable decrease in temperatures across the northern half of the country.

Between Wednesday and Thursday the entry of a perturbation of Atlantic origin will reach the central and northern regions, bringing the return of rain and thunderstorms.

Regional temperature swings in Rome and central Italy

In Lazio and central Italy, clear skies and elevated temperatures will characterize the beginning of the week. Daytime readings in Rome are forecast to reach 30°C to 31°C on Monday and Tuesday, which is 3 to 4 degrees above the seasonal benchmark. Meteorologist Flavio Galbiati noted that while central areas will see increasing cloudiness on Wednesday, the main Atlantic front could reach the central Tyrrhenian coast and Lazio on Thursday. If the weather deterioration materializes, daytime high temperatures in Rome will drop back to 26°C or 27°C before the front moves away on Friday.

On Monday and Tuesday across all of central Italy, and in particular over Lazio, stable weather is forecast, with clear or partly cloudy skies and moderate summer temperatures, but in Rome we could reach 30-31 degrees.

Low-pressure system monitored in the lower Mediterranean

Meteorological models are tracking a separate low-pressure system forming across the lower Mediterranean Sea north of Libya. Forecasters note that warm sea surface temperatures in the southern basin are providing the thermal energy and latent heat required to feed the disturbance. The system could gradually evolve into a tropical-like cyclone, often termed a Medicane or Mediterranean hurricane, featuring a well-defined eye surrounded by storm-force winds. While northern Italy manages the Atlantic frontal system from 16 September, meteorologists continue monitoring whether residual instability will affect the Ionian coast and the far south.