Sea Temperature in Mljet Island in June (2026) – Swimming Guide
Sea temperature in Mljet Island in June averages 24.3°C (typical range 21.7°C–27°C). Swimming conditions, 10-day trends, and top beaches.
Typical Range: 21.7°C – 27°C
Standard swimwear. Great for 30–60 minute continuous swims without any chill.
Povoljni termički uvjeti za cjelodnevni boravak uz more
4 rainy days · UV Index 9
Sea Temperature Progression in June by Decade
Multi-year oceanographic measurements across early, mid, and late month:
Annual Oceanographic Climatology for Mljet 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 | 14.2°C (12.6° – 15.7°) | 13.1°C | 6.7°C | 5 h | 8 d | Crisp & cool |
| February | 13.4°C (11.8° – 14.8°) | 13.6°C | 7°C | 5.8 h | 7 d | Crisp & cool |
| March | 14.4°C (12.8° – 16°) | 16.2°C | 9.2°C | 7 h | 7 d | Crisp & cool |
| April | 16.6°C (15° – 18.8°) | 19.8°C | 12.3°C | 8.5 h | 7 d | Crisp & cool |
| May → | 20.2°C (18° – 22.7°) | 24.5°C | 16.6°C | 10 h | 5 d | Refreshing & invigorating |
| June → | 24.3°C (21.7° – 27°) | 28.8°C | 20.4°C | 11.5 h | 4 d | Comfortable & warm |
| July → | 26.6°C (24.7° – 29°) | 31.8°C | 23.2°C | 12.5 h | 2 d | Very warm & ideal |
| August → | 27.6°C (25.6° – 30°) | 31.7°C | 23°C | 11.8 h | 2 d | Very warm & ideal |
| September → | 25.3°C (23° – 27.4°) | 26.8°C | 18.8°C | 9.4 h | 4 d | Very warm & ideal |
| October → | 21.9°C (19.8° – 24.2°) | 21.9°C | 15°C | 7.2 h | 7 d | Comfortable & warm |
| November | 18.2°C (16.2° – 20°) | 17.1°C | 10.7°C | 5.2 h | 9 d | Refreshing & invigorating |
| December | 15.4°C (13.7° – 17°) | 13.7°C | 7.6°C | 4.4 h | 8 d | Crisp & cool |
Top Rated Beaches in Mljet Island for this Season
Curated bathing spots featuring verified water cleanliness and supreme swimming comfort (8 verified locations):
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 Mljet Island
Is it warm enough to swim in Mljet Island in June?
In June, average sea temperature in Mljet Island is 24.3°C. Comfortable & warm / Recommended for all swimmers. Standard swimwear. Great for 30–60 minute continuous swims without any chill.
What is the air temperature and daily sunshine in June?
Average daytime air temperature reaches 28.8°C (20.4°C at night), featuring approximately 11.5 hours of bright sunshine daily and only 4 rainy days.
How does sea temperature evolve from early to late June?
During early June (1st–10th) water averages 23.5°C, mid-month (11th–20th) sits at 24.3°C, and late month (21st–31st) reaches 25.1°C.