Fourth heatwave of 2026 to push Italy temperatures to 41°C from mid-week
An African anticyclone will drive temperatures to 40-41°C in Tuscany and the Po Valley, with minima staying above 25°C, as the country's fourth major heat event of the summer takes hold from 29 July.
Early-week instability gives way to high pressure
A cold drop stationed over the lower Tyrrhenian Sea will keep conditions unsettled across southern Italy through Wednesday. Sicily and the southern Tyrrhenian regions will see scattered showers and afternoon thunderstorms, while the north and centre remain mostly sunny and gradually warmer. From 29 July the African anticyclone will reassert itself, extinguishing the last instability and locking in clear skies, strong sunshine and rising humidity along coasts and plains.
Ci troveremo di fronte a un'ondata di calore particolarmente intensa.
Temperature forecast: 40°C peaks and tropical nights
Once the high pressure settles, daytime maxima will climb well above the seasonal norm. The central-north interior plains will reach 36-38°C, with Florence and parts of the Po Valley touching 40-41°C by the weekend. Rome will see 35-38°C, and the urban heat island effect will push readings even higher inside the capital. Nighttime minima will not drop below 25°C, producing what forecasters call super tropical nights. The zero-degree isotherm will rise to 4,500 metres, roughly 1,000 metres above the July average.
I modelli matematici danno ormai tutti la conferma di una nuova ondata di caldo, una delle più intense e prolungate, la quarta dell'estate 2026. Bisognerà fare attenzione, perché vivremo delle giornate particolarmente eccezionali dal punto di vista termico, saranno almeno una decina.
- Florence
- 41 °C
- Po Valley
- 41 °C
- Rome
- 38 °C
- Central-North plains
- 38 °C
Duration and health alerts
The heatwave is forecast to persist at least until 7 August, with current simulations showing a solid high-pressure structure and no significant breakdown. The Ministry of Health issued a red alert for Campobasso on 27 July, and many green and yellow warnings will turn orange in the following days as the heat intensifies. The prolonged stretch of extreme temperatures, combined with high humidity, will create notable discomfort, especially in urban areas.
- Cold drop brings thunderstorms to Sicily and southern Tyrrhenian regions
- Sunny and warmer in north and centre, storms persist in Sicily
- African anticyclone takes hold; temperatures rise to 36-38°C in central-north plains
- Peak heat: 40-41°C in Tuscany and Po Valley, tropical nights widespread
- Heatwave persists at least until 7 August, no significant breakdown in sight
Climate context: record-warm oceans and El Niño
The heat arrives against a backdrop of record global ocean warmth. The European Copernicus service recorded an average sea surface temperature of 21°C, the highest since measurements began in 1979 and 0.6°C above the norm. El Niño is strengthening and is expected to exceed 3°C between autumn 2026 and early 2027, adding further thermal energy. In Veneto, the first half of summer (1 June to 20 July) averaged 23°C, surpassing the previous record of 22.7°C set in 2003 and 2022.
Questa ci sembra un'estate anormale, ma in realtà non ci saranno più estati normali, perché il cambiamento climatico sta correndo così in fretta.
In Spain and France, 300,000 people remain in shelters after fleeing wildfires that destroyed 240 homes and injured 84 firefighters. The flames are now approaching Bordeaux, and the rising temperatures will further challenge containment efforts.
