Sea Water Temperature in Croatia: Cities & Islands Guide (2026)
Official oceanographic sea water temperatures across 50 popular destinations in Croatia. Monthly swimming conditions (May to October), averages, and seasonal verdicts.
Adriatic Sea in July and August
Optimal swimming conditions
35 coastal cities and 15 islands
Adriatic Swimming Season by Month
Overview of swimming conditions in the Adriatic Sea across 6 key seasonal months (May to October).
May
18°C – 20°CStart of the Adriatic bathing season. Refreshing, crystal-clear water, ideal for active swimmers and quiet spring shores.
June
22°C – 24°COutstanding swimming conditions. Long sunny days, warm and comfortable sea for all ages, and peaceful early-summer beaches.
July
25°C – 27°CPeak summer season. The Adriatic is warm and inviting, perfect for extended swimming sessions, water sports, and family beach holidays.
August
25.5°C – 27.5°CWarmest sea temperatures of the year. Maximum accumulated heat, calm waters, and flawless conditions for swimming and diving across all regions.
September
23°C – 25°CIndian summer on the Adriatic. The sea retains its summer warmth while air temperatures turn pleasantly mild—widely regarded as the best month for swimming.
October
20°C – 22°CPleasant conclusion to the swimming season. The sea remains warmer than in spring, especially in Dalmatia and southern islands on sunny afternoons.
Sea Temperature by Destination (50 Stations)
Complete sea temperature guides by destination with monthly breakdowns and links to local beach guides.
📍 Northern Adriatic (Istria & Kvarner) (22)
Rovinj
Poreč
Pula
Opatija
Crikvenica
Rijeka
Umag
Medulin
Kraljevica
Funtana
Novi Vinodolski
Senj
Labin & Rabac
Fažana
Vrsar
Novigrad
Lovran
Mošćenička Draga
Krk Island
Rab Island
Lošinj Island
Cres Island
📍 Central Adriatic (Zadar & Šibenik Regions) (12)
Zadar
Šibenik
Vodice
Primošten
Rogoznica
Biograd na Moru
Novalja
Pag Island
Murter Island
Ugljan Island
Pašman Island
Dugi Otok Island
📍 Southern Adriatic (Split & Dubrovnik Regions) (16)
Dubrovnik
Split
Makarska
Trogir
Omiš
Baška Voda
Tučepi
Cavtat & Konavle
Orebić (Pelješac)
Kaštela
Brač Island
Hvar Island
Korčula Island
Čiovo Island
Mljet Island
Vis Island
Adriatic Sea Temperature Comparison Table (DHMZ)
Official multi-year climatological sea temperature averages (DHMZ / IZOR) for 10 key Adriatic hubs by month.
| Destination | May | June | July | August ★ | September | October | Peak |
|---|---|---|---|---|---|---|---|
| 🌡️ Rovinj | 18.5°C | 22.7°C | 25.3°C | 25.7°C | 23°C | 19.3°C | Very warm & ideal |
| 🌡️ Pula | 18.5°C | 22.7°C | 25.3°C | 25.7°C | 23°C | 19.3°C | Very warm & ideal |
| 🌡️ Krk Island | 18.3°C | 22.5°C | 25.1°C | 26.1°C | 23.4°C | 19.7°C | Very warm & ideal |
| 🌡️ Lošinj Island | 18.4°C | 22.6°C | 25.2°C | 26.2°C | 23.5°C | 19.8°C | Very warm & ideal |
| 🌡️ Zadar | 19.4°C | 23.5°C | 25.9°C | 26.2°C | 23.8°C | 20.3°C | Very warm & ideal |
| 🌡️ Šibenik | 19.5°C | 23.6°C | 26°C | 26.3°C | 23.9°C | 20.4°C | Very warm & ideal |
| 🌡️ Split | 20.2°C | 24.3°C | 26.6°C | 27°C | 24.7°C | 21.3°C | Very warm & ideal |
| 🌡️ Hvar Island | 20.1°C | 24.2°C | 26.5°C | 27.5°C | 25.2°C | 21.8°C | Very warm & ideal |
| 🌡️ Korčula Island | 20.1°C | 24.2°C | 26.5°C | 27.5°C | 25.2°C | 21.8°C | Very warm & ideal |
| 🌡️ Dubrovnik | 20.4°C | 24.5°C | 26.8°C | 27.2°C | 24.9°C | 21.5°C | Very warm & ideal |
Expert Swimming & Marine Tips
🌬️ Winds & Marine Currents
Summer afternoons regularly welcome the refreshing Maestral (NW) sea breeze. A strong Bura (NE) wind can temporarily drop surface water temperatures by 1–2°C, especially in shallow coastal coves.
☀️ Sun Protection & UV Exposure
In peak summer months, the UV index regularly surpasses 8. Limit unprotected sunbathing between 11:00 AM and 4:00 PM, and always use high-factor water-resistant sunscreen.
🤿 Water Clarity & Sea Urchins
The Adriatic Sea here consistently scores excellent water quality under EU bathing water directives. Sea urchins on rocky shallows serve as nature’s bio-indicator of immaculate water purity.
Frequently Asked Questions: Sea Water Temperature in Croatia
When is the Adriatic Sea warm enough for swimming in Croatia?
The swimming season in Croatia begins in late May when sea temperatures reach 19°C to 21°C. The prime swimming season runs from June through September, with water temperatures ranging from 23°C to 27°C. July and August offer the warmest conditions, ideal for swimming. Swimming remains very pleasant into October, especially in southern Dalmatia.
Which region in Croatia has the warmest sea water?
Southern and Central Dalmatia (including Split, Hvar, Korčula, and Dubrovnik) generally record the highest sea temperatures, averaging 25°C to 27°C in peak summer. However, shallow sheltered bays in Istria and Kvarner (such as Medulin) can heat up rapidly during sunny summer days, occasionally exceeding 28°C.
How is sea temperature measured in Croatia?
Official measurements are conducted by the Croatian Meteorological and Hydrological Service (DHMZ) and the Institute of Oceanography and Fisheries (IZOR). Temperatures are measured at a standardized depth of 2 meters at 07:00, 14:00, and 21:00 local time, preventing surface distortion from direct solar radiation.
Do coastal winds like Bura or Jugo affect sea temperature?
Yes, wind plays a major role. Strong north-easterly Bura winds push warm surface water offshore, triggering upwelling of cooler deep water that can drop coastal sea temperatures by 2°C to 4°C in a few hours. Conversely, southerly Jugo winds push warm water toward the coast and mix the sea evenly.