Italy faces yellow alerts across seven regions before late-summer anticyclone arrives

Yellow alert across southern regions

Civil Protection authorities issued a yellow weather alert for Friday, 25 September across seven central and southern regions in response to an incoming cold air front. The warning covers Abruzzo, Basilicata, Calabria, Campania, Molise, Puglia, and Sicily for anticipated thunderstorms and hydrogeological risks, with Calabria also flagged for hydraulic hazards. Meteorologists forecast that rain and localized storms will move from Romagna and Marche into the central Adriatic coast, Lazio, and southern territories before dissipating by Friday evening. Strengthening northern winds, including Bora and Grecale, will accompany the front across the Adriatic and southern basins. Daytime maximum temperatures on Friday will reach up to 25°C in the north and between 26°C and 27°C across central and southern areas, while nighttime lows will hover near 15°C in central and northern sectors.

Weekend anticyclone and temperature rebound

Atmospheric pressure will rise rapidly heading into the weekend as the low-pressure system moves east toward the Aegean Basin. Lingering morning showers on Saturday, 26 September will remain confined to Calabria and Sicily before clearing substantially in the afternoon, while the rest of the country experiences widespread sunshine. Winds from the north will gradually subside by Sunday, 27 September, allowing a subtropical ridge to extend over the peninsula. Daytime high temperatures on Sunday will climb to between 27°C and 28°C in central regions. Clear night skies will simultaneously cause nocturnal cooling, with overnight lows dropping to between 12°C and 13°C in the north and center, and between 15°C and 16°C in the south.

Head meteorologist at iLMeteo.it Lorenzo Tedici detailed the atmospheric progression ahead of the weekend.

In the coming hours we will see a partial increase in cloud cover over the Alps and Tyrrhenian regions, with light scattered showers developing later on Thursday in the northeastern mountains and over Sardinia. A cool air mass moving down from Central Europe will reach Italy overnight between Thursday and Friday.

Omega block and late-summer warmth

High atmospheric pressure will dominate weather patterns during the final days of September through an Omega block configuration positioned between stationary low-pressure systems near Portugal and Greece. This synoptic structure will draw warm air from North Africa across Western and Central Europe. Forecast models project daytime temperatures running 2°C to 4°C above seasonal norms across central and southern Italy, with northern regions experiencing positive thermal anomalies of about 5°C. Maximum temperatures will reach between 27°C and 28°C in northern areas and between 29°C and 30°C across central and southern regions, while localized peaks on Tuesday, 29 September will reach up to 31°C in Sardinia.

Autumn shift in early October

Forecast models indicate a transition toward typical autumn weather starting on Thursday, 1 October as the Mediterranean opens to Atlantic storm tracks. The stable anticyclone will break down under the influence of two distinct low-pressure disturbances affecting Italian territory simultaneously. A cyclonic system moving from southeastern Europe toward Greece and the Balkans will bring rain to southern regions. Simultaneously, an expansive northern European trough extending toward the Iberian Peninsula will affect northwestern Italy, Sardinia, and the Tyrrhenian coastline through Friday, 2 October. Medium-range projections from the European Centre for Medium-Range Weather Forecasts confirm an overall seasonal pattern of above-average temperatures alternating with periodic frontal passages.