Worst time to visit Greece

For most travellers, the worst month to visit Greece is August

August combines everything that makes a Greek summer hard: 33°C average days in Athens with heatwaves that push past 40°C, the year's highest wildfire risk, the August 15 national holiday when Greeks fill every ferry and island room, and the highest prices of the year. July is nearly identical and, on the thermometer, hotter still — a 35°C average in Athens.

The Acropolis closed during the hottest hours of the day in the July 2023, 2024, and 2025 heatwaves, and the Ministry of Culture now treats midday closures as standard heatwave policy. Wildfires forced mass evacuations on Rhodes (July 2023), on Evia (August 2021), and near Athens (August 2024). In the Cyclades, the meltemi — a dry northerly that blows hardest in July and August — cancels ferries for a day or two at a time.

Why July and August are genuinely difficult

• Heat.Athens averages 35°C in July; heatwaves of 40–44°C have become an annual event. The islands run a few degrees cooler thanks to the sea breeze, but Santorini's caldera path at 2pm is still brutal. Watch the Hellenic National Meteorological Service for heatwave warnings.
• Wildfires. Bone-dry summers (9mm of rain in July) and strong winds make July–August the fire season. Evacuation alerts arrive by the 112 system — register your phone on arrival.
• Crowds and prices. July and August take 42% of the year's tourist-accommodation nights in Greece (Eurostat, 2025). Santorini and Mykonos are saturated; Athens hotel rates and island rooms peak; the August 15 weekend is the busiest travel period of the Greek year.
• The meltemi. A dry northerly that gusts to 60–70 km/h across the Cyclades, closing beaches on the north side of each island and cancelling ferries.

For island trips, the other worst time is January and February

The Atlas Ranger Score puts January at the bottom on pure numbers — 13°C days, 62mm of rain, and the year's shortest sunny days — but the real problem is that the islands are shut:

• Most hotels, tavernas and rental shops on the Cyclades close from November to March
• Ferry schedules drop to a skeleton service; some routes stop entirely
• Santorini and Mykonos are near-empty — atmospheric for a few hours, dead for a week
• Athens is cold, grey, and wet — but its museums, food, and hotel rates are at their best

Crete, Rhodes, and Corfu have enough year-round population to stay partly open, and Athens with Thessaloniki is a genuinely good winter city trip. But a winter island-hop is the one Greek itinerary that simply does not work.

If you have to travel in high summer, here's what to do

• Book the Acropolis for 8am. Timed tickets open the gate at 8; be there then, and be done by 10. Same for Delphi, Knossos, and Ancient Olympia.
• Choose the Ionian or the Sporades over the Cyclades. Corfu, Kefalonia, and Skopelos are greener, cooler, and sheltered from the meltemi.
• Avoid August 13–17 for any ferry travel. Book cabins and cars months ahead if you must move on those dates.
• Register for 112 emergency alerts on arrival — wildfire evacuation notices go out by SMS in English.
• Plan the middle of the day indoors or in the water — museums, long lunches, or a beach with shade — and save walking for after 6pm.

Better windows: when to visit instead

• May:The sweet spot — 25°C days, 12 hours of sun, every island route running, prices well below summer. The sea is a cool 20°C by month's end.
• September: The other sweet spot — 29°C days, the warmest sea of the year (25°C), the meltemi fading, and crowds easing after the first week, though the month as a whole is still about as busy as June. The best month for swimming.
• April and October: Mild, uncrowded, and cheap, with the islands opening (April) or winding down (October). Orthodox Easter — usually April — is the best cultural week of the year.

Click any month on the seasonality map above for the full climate detail and our verdict.