The return of warm weather is taking hold across France, and especially in Île-de-France (75, 77, 78, 91, 92, 93, 94 and 95) in this first half of September 2026. After a cool, stormy end to August, a high-pressure ridge is pushing hot air up from the south, with a peak expected this weekend of September 5-6. The lingering question after a record summer remains: can we call this a new heatwave in Paris?
According to Météo-France, temperatures are rising noticeably in Paris and in Île-de-France, though not reaching the extremes of the South. We can expect around 29°C this Friday, September 4, about 27°C on Saturday the 5th, then 31–32°C on Sunday the 6th, with a possible risk of thundery showers late in the day.
Heat persists on Monday the 7th (around 30°C) before easing on Tuesday the 8th (about 25°C), then returning to seasonal levels on Wednesday the 9th (roughly 23°C). The mornings, meanwhile, stay mild, between 17 and 19°C.
The answer is leaning toward “no” for the Île-de-France region. The expected highs (29 to 32°C) far exceed early-September normals (around 23°C), but remain well below the alert thresholds for the south of the country.
More than anything at this time of year, the nights grow longer and the mercury falls enough (17 to 19°C by dawn) to avoid meeting the criteria for a heatwave, which requires high minimums for several consecutive days. So we’re looking more at a late spell of warm weather than a confirmed heatwave. The day-by-day details can be found in our Île-de-France weather update of the week.
The situation is very different further south. On September 3, 2026, Météo-France placed several departments—Aude, Ardèche, Drôme, Gard and Hérault—under an orange heatwave alert starting Friday, September 4.
An orange heatwave alert in September remains a very rare event, last observed in 2023. Temperature spikes could approach 37 to 40°C, well above what the Île-de-France typically experiences. The official, continuously updated map can be viewed on the Météo-France site.
This heatwave comes with very little precipitation, worsening the drought that already affects the region and the entire country. It is probably the most tangible consequence of this episode for Île-de-France residents, more than the heat itself.
If the heat waves persist this weekend, it’s wiser to shift long outdoor activities to the cooler parts of the day and opt for shade and air-conditioned spaces, such as the museums and exhibitions of Paris and Île-de-France, all while staying well hydrated. For day-by-day updates, the most reliable source remains Météo-France, refreshed daily. Also keep in mind the summer of 2026 and its fifth heat wave, to gauge the progress toward finally milder temperatures.
Dates and Opening Time
From September 4, 2026 to September 8, 2026
