Italy faces severe weather split with northern downpours and southern heat reaching 40°C

Atlantic storm system over northern regions

An Atlantic low-pressure system is dividing Italy into two distinct weather regimes as it moves across the peninsula on 21 August 2026. Heavy downpours will hit Liguria and Lombardy before expanding across the entire northern territory and reaching Tuscany by the evening. Forecasters expect Lombardy to record rainfall approaching 100 liters per square meter, while Liguria and sections of Tuscany will exceed 70 millimeters. This volume concentrates an entire summer month of precipitation into a single 24-hour period. Lorenzo Tedici of iLMeteo.it explained the impact of the initial precipitation band across northwestern terrain.

We expect up to 30 to 50 mm of rain in 24 hours, especially between Lombardy and Piedmont. We are talking about 50 liters of water for each square meter of soil: relief from drought and to prevent the outbreak of new fires.

Temperature drops and severe storm risks

The incoming front will trigger a sharp downward adjustment in northern temperatures on Friday. Thermometers in Milan, Turin, and Venice will peak near 24°C, representing a reduction of 8 to 10 degrees compared to the previous week. Meteorology specialists note that Mediterranean sea surface temperatures hovering near 30°C provide substantial thermal energy when interacting with incoming Atlantic air masses. This thermal contrast creates conditions capable of generating intense downpours of 200 millimeters within two hours and electrical activity reaching 8,000 lightning strikes per hour. Local areas also face the threat of downburst winds that can unroof buildings and fell mature trees.

Intense heat and health alerts in the south

In contrast to the northern cooling, southern Italy and the surrounding islands will remain under the influence of a subtropical African anticyclone. Daytime temperatures will reach 38°C to 40°C across Puglia, Campania, Basilicata, Calabria, and Sicily, with southern Sardinia seeing values between 37°C and 39°C. The Italian Ministry of Health declared orange heat alerts on Friday across Bari, Campobasso, Palermo, and Pescara. Conditions will escalate on Saturday 22 August as Bari and Palermo move to level 3 red emergency alerts, while yellow alerts cover nine cities including Rome, Naples, and Catania. Climatologist Giulio Betti assessed the geographical split affecting the country.

In these days there will be a turning point in the Centre-North, therefore northern regions, Tuscany, partly also Umbria and Upper Lazio which will see a structured drop in temperatures, with values that will drop starting from Friday 21 August. I would say that we can consider extreme heat to be over, which does not apply to the South and Sardinia.

Outlook for late August and returning anticyclone

Weather conditions will stabilize briefly across the country over the weekend of 22 and 23 August 2026. Northern regions will experience clearer skies, interrupted only by isolated showers across the north-east on Saturday afternoon. A subsequent Atlantic disturbance is projected to reach northern Italy and Tuscany between the night of Monday 24 August and Tuesday 25 August, bringing renewed rainfall and below-average temperatures. By Wednesday 26 August, a broad subtropical ridge originating in inland Tunisia and Algeria will expand across the Mediterranean basin. This pattern will restore sunny conditions and elevate southern temperatures above 35°C through late August.