The month of September opens with a complex and fascinating atmospheric picture in Tuscany, alternating signals of a return to traditional seasonality with thermal persistences inherited from the exceptional summer just ended. On the morning of Tuesday, September 1, the Centro Meteo Toscana released a long analysis that precisely describes the ongoing evolution, highlighting the presence of two climatic “tracks” that are characterizing the start of the month.
The first track: September normality
“September runs on a double track – explains the Cmt –. On the first, a perfectly normal development for early September. That is, days of sunshine and warmth that often gradually accompany us towards the change of season. The famous “September summer”.” According to Centro Meteo Toscana, this first scenario recalls the typical dynamics of the past: the “summer break” right after Ferragosto, the return of the Azores anticyclone, and a climate alternating stability and brief unstable phases, just as it happened decades ago. A context that, despite some episodes of heat, fully fits within the physiology of the period.
The second track: three degrees too many
“The second track instead – continues the Centro Meteo – brings with it those three degrees too many that we have been carrying for weeks now.” The Cmt emphasizes how the real anomaly is not so much the structure of the days, but the temperature: a thermal surplus of about 3°C that continues to manifest in daily highs. A legacy of summer 2026, defined by experts as “probably the hottest experienced in the last 200 years in the central western Mediterranean.” This thermal gap translates into highs that, instead of the traditional 29‑30°C of twenty years ago, today reach 32‑33°C. And that, between Friday, September 4 and Monday, September 7, could rise up to 35‑36°C, even in an atmospheric context considered “normal” for a late summer North African resurgence.
The call to climatic history
“History therefore tells us that since mid-August the atmosphere has resumed its normal path. But with those three degrees too many that we carry due to an extreme summer and that we probably will not see again soon,” continues Centro Meteo Toscana. The analysis invites caution in long-term forecasts: while it is true that many fear increasingly hot summers, it is equally true that climatic history shows long and complex cycles. The comparison with 2003 is emblematic: after that exceptional summer, an immediate repeat in the following years was hypothesized, but it took 23 years to see similar conditions again.
The forecasts for the coming days
Centro Meteo Toscana then goes into the details of the forecasts in Tuscany: “Fair weather dominated by the Azores anticyclone until Thursday, September 3 inclusive, with afternoon breezes and some unstable hints in the Apennines. Highs around 32/33° degrees in the inland areas.” The week will continue with generally stable conditions until Thursday, with pleasant days especially along the coast and some unstable episodes in the border Apennine areas. “Friday, September 4, attempt of a North African anticyclone resurgence with a sharp thermal rise and peaks up to 35/36° degrees. It is not excluded that some September thermal records may emerge. Torrid climate,” warns the Cmt. The heat peak will arrive precisely on Friday, with values that could approach or exceed local records for the month of September. “From Saturday, September 5 to Monday, September 7 still very hot for the period but with slightly lower temperatures. The whole structure will gradually become more humid.” The weekend will still be hot, but with a progressive increase in humidity and the arrival of the sirocco along the coast.
Instability arriving
“From Tuesday, September 8 or Wednesday, September 9 increasingly unstable weather with the passage of two or three unstable fronts and the chance for several thunderstorms during the rest of the week.” Centro Meteo Toscana therefore forecasts a more decisive change in the second half of next week, with the entry of more unstable fronts and the possibility of widespread thunderstorms, marking the start of a more dynamic and typically autumnal phase.
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