May is one of the two best months in Split: highs around 23 °C, nine hours of sun a day and Sudamja, the city's feast day, on 7 May. The sea averages about 18 °C — cold early in the month, swimmable for most people by the last week.
By Marin Perić
Yes — with September, it is the month we would pick. Everything is open, the days run past eight in the evening, and the heat has not yet arrived: the average high is 23.4 °C and there is less than one 30 °C day in a typical May. Crowds build through the month — Split Airport handled about 406,000 passengers in May 2026, double April — but they are still well short of July. The only question is the sea, and the answer depends on which week you come.
At DHMZ's Split-Marjan station May averages a high of 23.4 °C and a low of 16.1 °C. Rain falls on about six days, totalling 58 mm, and usually as short showers rather than grey days. Sunshine is nine hours a day. About eleven days in an average May reach 25 °C, which is warm enough to want shade at lunchtime but not enough to wreck an afternoon.
By the end of the month, yes. The sea averages about 18 °C across May, but that average hides a climb: early May water is still close to April's, and by the last week it is usually around 20 °C. The ten-year range runs from roughly 15 °C to 24 °C. If swimming is the point, come in the second half.
Where to swim first: the best beaches in Split.
Sudamja is the feast of St Domnius, Split's patron saint, and the city's own day. The day before, his sarcophagus in the cathedral is opened and the relics taken out. On 7 May a procession leaves the cathedral at 10:00 behind a silver bust holding the relics, goes out through the palace's eastern gate past the market and on to the Riva for Mass, followed by officials, parishes and thousands of people from Split. The Sudamja fair fills the waterfront and the streets around it on 6 and 7 May — the old custom is to buy something wooden to take home. In 2026 the wider programme of concerts ran from 30 April to 10 May.
Dates and details: the Feast of St Domnius.
Where it all starts: the Cathedral of St Domnius.
Everything in town is open, including beach bars at Bačvice and below Marjan.
Boat trips run daily in settled weather, including the Blue Cave and five-island route.
The state catamaran to Hvar town moves to its summer timetable on 29 May (in 2026), with a morning departure from Hvar and a 17:00 sailing from Split, at a summer fare of €10.
Krka is at its €20 spring price for adults, with the Skradin boat running. It rises to €40 in June.
1 May — Labour Day, a public holiday.
30 May — Statehood Day, a public holiday.
Corpus Christi, a public holiday that moves with Easter — 27 May in 2027.
This is the month for doing everything once. A boat day to the Blue Cave before the summer queues. Krka before the price doubles. The first swim of the year at Kašjuni, under the pines on the south side of Marjan. Long evenings on the Riva and at Sustipan, where the sunset now comes after eight.
See the Blue Cave and five islands,
Kašjuni beach and
Rooms for the Sudamja week and for late May, which fills earlier than people expect. Boat trips a few days ahead — the small-group ones sell out first. A table for 7 May, when half of Split eats out.
Comparing months? Read Split in spring 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.