Where to go in September
If one month had to be defended as the best of the year, it would be this one. Eleven of the twelve entries touch the ceiling and the list is almost wholly Mediterranean and Atlantic — Madrid, Corsica, Nice, Santorini, the Algarve, Lisbon, Madeira, Tenerife — with Algiers and Essaouira on the African shore of the same sea, and Istanbul and Cappadocia at its eastern edge. Three good things coincide: the water is at its warmest after a summer of heating, the air has come back down towards 25 to 27 °C, and the crowds disperse sharply once schools reopen in the first week. Prices follow, visibly from the second. The trap is at the margins: autumn rain settles in the north, so the further you stray from this belt the more a single bad week costs, and daylight shortens fast.
The ranking for September
Three of them in detail
Lisbon — Portugal
Lisbon takes 27.1 °C in the afternoon and 17.9 °C at night, with three days above 1 mm and 23 mm. Its good season runs seven months, from April to October. The airport is 5 km from the centre, which makes a two-night stay genuinely defensible.
Corsica — France
Corsica maintains 27.1 °C by day and 16.2 °C at night, five days of rain for 50.1 mm: September is not dry here, and the wettest month is still ahead, in November. At 1,000 on our index the island is the French yardstick itself. Ajaccio sits 5 km from its airport.
Essaouira — Morocco
Essaouira gives 25.4 °C and 18.1 °C without one day above 1 mm, for 3.2 mm of water. It registers 27 days of rain across an entire year and its good season covers all twelve months: the Atlantic wind, not the sun, sets the tone. The airport is 14 km from the ramparts.
What to avoid this month
Five rain alerts and not one for heat. Kerala counts 29 days above 1 mm and Goa 26 as the monsoon withdraws, Lagos 24 for 199.8 mm. Reykjavik opens its autumn on 15 days of rain and 137.6 mm, and Bled takes 14 for 177 mm.
How the score is calculated
One formula, applied identically to the hundred places, on measured station records:
score = 100 − 3·max(0, |tMax − 25| − 3) − 4·max(0, rainyDays1 − 6) − 2·max(0, 12 − tMin)A place is flagged as one to avoid when it records 14 rainy days or more in the month, an average high of 34 °C or more, or an average high of 8 °C or less. Only the five lowest-scoring flagged places are listed.
Updated on 21 September 2026