After weeks of instability, cool temperatures and frequent rains – concentrated especially in the North – the main global forecast models, ECMWF and GFS, converge towards a common scenario: between the end of May and the first days of June, Italy will experience its first real heat wave of 2026.
The mechanism underlying the African heat
Driving this turning point will be the expansion of the African subtropical anticyclone over the central Mediterranean, triggered by an atmospheric pattern that has now recurred in recent summers. A depression positioned between Portugal and western Spain will act as a real “heat pump”, channeling masses of Saharan air towards Southern Europe. A configuration that in recent years has repeatedly triggered phases of intense and prolonged heat, involving not only Italy but also Spain, France and Germany.
First a taste, then the peak
The weekend just ended has already offered a foretaste of summer, with temperatures of 30-32°C in the Po Valley and in the internal valleys of the Centre. But the most critical moment is expected at the end of May, when a new, more intense wave will hit the North-West, Sardinia and Sicily in particular, with peaks above 35°C in the internal areas. Values between 28 and 32°C are also expected in Puglia, Calabria, Basilicata and Campania, with temperatures above average also in the Center and North.
Accompanying the heat: predominantly clear skies, dry air and possible transport of Saharan dust at altitude, responsible for that characteristic milky color of the sky. Thermal discomfort will be more marked in the central hours, especially in cities and along the southern coasts and islands.
A fully summery end of May
The agreement between the models strengthens the credibility of this scenario, while leaving room for uncertainty about the exact duration and intensity. What appears increasingly likely is that, after a start to the season that was anything but summery, the South and the Islands will reach typically summer conditions by the end of the month, with a marked improvement also in the North-West.
