The short answer
For most trips, the best months are May, June, September and early October. The weather is warm, the sea is swimmable for much of that period, island ferries and businesses are running, and the crowds and heat are lower than in July and August. Winter suits city and museum trips to Athens and Thessaloniki, but many island hotels and tavernas close.
Greece is a large country, and the mainland mountains, Crete and the northern islands have different climates. The figures below use central Athens as a reference point; the islands are usually a little milder in summer because of the sea breeze, and the north is cooler and wetter in winter.
Average temperatures and rainfall in Athens
Based on 1991 to 2020 averages for downtown Athens:
| Month | Average high | Rainfall |
|---|---|---|
| January | 13°C | 56 mm |
| March | 17°C | 46 mm |
| April | 21°C | 28 mm |
| May | 27°C | 21 mm |
| June | 32°C | 12 mm |
| July | 34°C | 11 mm |
| August | 34°C | 5 mm |
| September | 30°C | 26 mm |
| October | 24°C | 39 mm |
| November | 19°C | 71 mm |
| December | 14°C | 76 mm |
August is the driest month and November and December the wettest. Summer rain is rare; winter brings storms rather than constant drizzle, with plenty of clear days in between.
Spring: April to early June
Spring is the best season for walking, archaeological sites and wildflowers. April can still be changeable, and the sea is cold for most swimmers until late May or June. Many island businesses reopen around Easter and are fully running by May.
Orthodox Easter is the biggest festival of the Greek year, with processions on Good Friday, a midnight service on Saturday and family feasts on Sunday. It usually falls on a different date from Western Easter: 12 April in 2026 and 2 May in 2027. Domestic travel is busy that weekend, and some sites and shops keep holiday hours, so book transport early.
Summer: mid-June to August
July and August are the hottest and busiest months. Average highs in Athens reach about 34°C, and heatwaves pushing well above 40°C have become more frequent. During heatwaves the authorities have closed archaeological sites, including the Acropolis, during the hottest hours, so plan outdoor sightseeing for early morning.
On the islands, the meltemi, a strong dry northerly wind, blows across the Aegean in midsummer. It keeps temperatures bearable but can make north-facing beaches rough and disrupt small boats and fast ferries. August is the peak month for Greek holidaymakers, especially around 15 August, the Dormition of the Virgin Mary, a major religious holiday. Ferries and island accommodation are at their busiest and most expensive.
Summer is also the wildfire season. Follow official alerts, respect any closures of forests or hiking routes, and act on the 112 emergency messages that the civil protection service sends to phones in affected areas.
Autumn: September to October
September is many travellers' favourite month: the sea is at its warmest after the summer, the meltemi weakens, and the school holidays have ended. October is cooler and less settled, especially later in the month, but it is still good for sightseeing and often for swimming in the south, including Crete and Rhodes. Island services begin to wind down from mid-October, and some ferry routes switch to reduced winter timetables.
Winter: November to March
Winter is low season. Athens and Thessaloniki stay lively, museums are quiet and hotel prices drop, but many state sites run shorter winter hours. On smaller islands, a large share of hotels, restaurants and tour services close, and ferry links are less frequent and more affected by storms. Mountain areas such as Epirus and the Peloponnese see snow, and there are ski centres on mountains including Parnassos.
Matching the season to the trip
- Island hopping and beaches: June and September, with May and early October as quieter options.
- Ancient sites and walking: April, May, late September and October.
- Athens city break: almost any month except the peak heat of July and August.
- Lowest prices: November to March, outside Christmas and New Year, accepting reduced island services.
