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🌊 DHMZ & Oceanographic Climatology Guide 2026

Sea Temperature in Čiovo Island in May (2026) – Swimming Guide

Sea temperature in Čiovo Island in May averages 20°C (typical range 17.8°C–22.5°C). Swimming conditions, 10-day trends, and top beaches.

🏖️ Explore all 11 beaches in Čiovo Island →
Annual Overview May 20°C June 24.1°C July 26.4°C August 27.4°C September 25.1°C October 21.7°C
🌡️ Average Sea Temperature
20°C

Typical Range: 17.8°C – 22.5°C

🏊 Swimming Comfort
Refreshing & invigorating / Best for active swimming

Standard swimwear is fine for quick dips. For toddlers and sensitive swimmers, a thin 2mm shorty wetsuit is recommended.

☀️ Air Temperature (Day / Night)
24.4°C / 16.5°C noć

Povoljni termički uvjeti za cjelodnevni boravak uz more

🌤️ Sunshine & Rainfall
10h sun hours / day

5 rainy days · UV Index 7

Sea Temperature Progression in May by Decade

Multi-year oceanographic measurements across early, mid, and late month:

1st – 10th May 19.2°C Early Month
11th – 20th May 20°C Mid Month
21st – 31st May 20.8°C Late Month

Annual Oceanographic Climatology for Čiovo Island

Multi-year historical records by the Croatian Meteorological and Hydrological Service (DHMZ) & Institute of Oceanography and Fisheries (IZOR)

Month Sea Temperature Day Air Night Air Sun Hours Rain Days Swimming Verdict
January 14°C (12.4° – 15.5°) 13°C 6.6°C 5 h 8 d Crisp & cool
February 13.2°C (11.6° – 14.6°) 13.5°C 6.9°C 5.8 h 7 d Crisp & cool
March 14.2°C (12.6° – 15.8°) 16.1°C 9.1°C 7 h 7 d Crisp & cool
April 16.4°C (14.8° – 18.6°) 19.7°C 12.2°C 8.5 h 7 d Crisp & cool
May → 20°C (17.8° – 22.5°) 24.4°C 16.5°C 10 h 5 d Refreshing & invigorating
June → 24.1°C (21.5° – 26.8°) 28.7°C 20.3°C 11.5 h 4 d Comfortable & warm
July → 26.4°C (24.5° – 28.8°) 31.7°C 23.1°C 12.5 h 2 d Very warm & ideal
August → 27.4°C (25.4° – 29.8°) 31.6°C 22.9°C 11.8 h 2 d Very warm & ideal
September → 25.1°C (22.8° – 27.2°) 26.7°C 18.7°C 9.4 h 4 d Very warm & ideal
October → 21.7°C (19.6° – 24°) 21.8°C 14.9°C 7.2 h 7 d Comfortable & warm
November 18°C (16° – 19.8°) 17°C 10.6°C 5.2 h 9 d Refreshing & invigorating
December 15.2°C (13.5° – 16.8°) 13.6°C 7.5°C 4.4 h 8 d Crisp & cool

Top Rated Beaches in Čiovo Island for this Season

Curated bathing spots featuring verified water cleanliness and supreme swimming comfort (11 verified locations):

View all 11 beaches in Čiovo Island →

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 Temperature in Čiovo Island

Is it warm enough to swim in Čiovo Island in May?

In May, average sea temperature in Čiovo Island is 20°C. Refreshing & invigorating / Best for active swimming. Standard swimwear is fine for quick dips. For toddlers and sensitive swimmers, a thin 2mm shorty wetsuit is recommended.

What is the air temperature and daily sunshine in May?

Average daytime air temperature reaches 24.4°C (16.5°C at night), featuring approximately 10 hours of bright sunshine daily and only 5 rainy days.

How does sea temperature evolve from early to late May?

During early May (1st–10th) water averages 19.2°C, mid-month (11th–20th) sits at 20°C, and late month (21st–31st) reaches 20.8°C.

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