Ionian Islands — Water Temperature Today and Throughout the Year
Discover water temperatures in Ionian Islands (Greece), with real-time data and annual trends. Find all locations in the region and check the water temperature in them. We find every place where you can swim and show you the water temperature there today and throughout the year.
Sea Water Temperature Along the Coast
Chart of Average Temperature Changes Over the Last 60 Days
Places with the Warmest Sea Water Today
The Most Popular Seaside Places
Coastal Seas and Oceans
Water Temperature in Lakes and Rivers
Popular Lakes
Water Temperature and Swimming Overview
Regions and Map
Water Temperature Trends
The Ionian Islands, located off the western coast of Greece, are renowned for their turquoise waters and mild climate. During the summer months (June to September), sea temperatures typically range from 24–27°C (75–81°F), providing ideal conditions for swimming, snorkeling, and other water activities. Beaches such as Navagio in Zakynthos, Myrtos in Kefalonia, and Porto Katsiki in Lefkada attract visitors with their warm, clear waters and stunning scenery.
In the spring (April to May) and autumn (October to November), the sea begins to cool slightly, with temperatures averaging 20–23°C (68–73°F). While the waters are not as warm as during the summer, they remain comfortable for swimming, especially for those accustomed to milder temperatures. These seasons also offer a quieter and more relaxed atmosphere, perfect for exploring the islands' natural beauty without the peak-season crowds.
Winter months (December to February) bring cooler sea temperatures, ranging from 14–16°C (57–61°F). While swimming is less common during this time, the Ionian Islands still provide opportunities for coastal walks, sailing, and enjoying the tranquil seaside environment. The region’s natural charm and warm hospitality make it an attractive destination throughout the year.