September is the month locals pick: the sea is about 23 °C — warmer than June — highs ease to around 25 °C, and the crowds thin noticeably after the first week. Boats and beach bars still run all month. The one change is more rain, usually as short storms.
By Marin Perić
Yes — on balance it is the best month of the year. The sea has been warming since May and holds its heat long after the air cools, so the water in September is warmer than in June. The midday heat breaks: there are only two or three 30 °C days in an average September. And the crowd changes: Split Airport handled about 558,000 passengers in September 2025, roughly the same as June and well down on August's 758,000, with families gone once the schools go back.
At DHMZ's Split-Marjan station September averages a high of 25.4 °C and a low of 18.4 °C. Rain makes a comeback: 82 mm, more than double August's, but on only about six days — it tends to arrive as a thunderstorm that clears within hours. Sunshine is still over eight hours a day. Sunset slides from about half past seven at the start of the month to before seven by the end.
Yes, all month. The sea averages about 23 °C, with a ten-year range of roughly 19 °C to 26 °C. The water is clear, the beaches have space again after the first week, and late-afternoon swims are as good as any in summer.
Where to swim: the best beaches in Split.
Everything runs through September: boats, beach bars, island konobas and every tour.
The state catamaran to Hvar town switches to its off-season timetable on 28 September (in 2026), with an afternoon sailing from Split and an early-morning return. Seasonal private lines keep running into October, so check the specific operator for late-month island days.
Krka stays at the €40 summer price until the end of September, then drops to €20 in October.
Cruise ships are still regular — Split logged 44 cruise visits in September 2025 — so check the port schedule if the palace is your main plan.
The month changes as it goes. The first week still feels like August — full beaches, summer prices, hot middays — while the last week feels like early autumn, with cooler evenings and the first boats coming off the water. In between is the sweet spot. One concrete marker: the state catamaran fare between Split and Hvar was €10 in the 2026 season and €6.40 once the off-season timetable began on 28 September, and Krka entry halves from €40 to €20 on 1 October.
The Split Film Festival, a festival of new film, is held in September — its 31st edition was in 2026. Beyond that, September is not an events month: it is a month for the sea and for the city settling back into its own pace. Hajduk's season is under way, and a match night at Poljud is a good evening out.
How to go: Hajduk at Poljud.
Everything you would do in summer, at a gentler pace. The Blue Cave and five-island run with calmer queues. Hvar or Brač by boat. Sunset cruises in warm evening air. Walking becomes pleasant again by the end of the month, so Marjan and Klis are back on the list.
See the Blue Cave and five islands,
the Šolta sunset swim cruise and
things to do in Split in autumn.
Rooms for the first half of September a good while ahead — it is popular for exactly the reasons above, and the first week still behaves like August. Boat trips a few days ahead. Restaurants are easier than in summer but still worth booking for weekends.
Comparing months? Read Split in autumn and
Where these numbers come from: air temperature, rain and sunshine are the 1991–2020 climate normals for the Croatian Meteorological and Hydrological Service (DHMZ) station at Split-Marjan, 122 m up on Marjan hill, as published by the World Meteorological Organization through NOAA. A rain day is one with at least 1 mm. Sea temperature is the ten-year average for Split from seatemperature.info. Daylight and sunset are for the 15th of the month. Passenger figures are from the Croatian Bureau of Statistics.
Get out there
Guided trips that include this stop, with live availability.
Boat trips
A full day on a fast twelve-seat boat: the Blue Cave on Biševo, the Monk Seal cave, Stiniva's famous cove, lunch on Vis and a swim off Budikovac's turquoise lagoon, finishing with a stop at Hvar town. Ten and a half hours, small group, no coach transfer.
History
Ninety minutes through the palace with a guide who lives inside it: the Golden Gate, the cellars, the Peristyle, the cathedral and the streets in between. Small group, no flag, and a proper explanation of why a Roman emperor retired to a cabbage patch in Dalmatia.
Boat trips
Five hours to Šolta and back on a ten-person boat: three swim stops in coves you cannot reach by road, an hour in Maslinica for dinner or a drink, and the run home across the channel as the sun goes down behind the island.