Travel time: Year-round
Greece is defined by a quintessential Mediterranean climate, though its complex geography of over 6,000 islands and rugged mountains creates significant regional diversity. Generally, the climate is characterized by hot, dry summers and mild, wet winters.
Daily weather behavior follows a predictable rhythm: mornings are typically calm and bright. By mid-afternoon, sea breezes (known as bourini in some regions) often pick up, providing relief from the peak heat. In coastal areas, the humidity remains manageable, but the intense Mediterranean sun means that the "feel-like" temperature can be significantly higher than the recorded air temperature during the afternoon hours (usually 2:00 PM to 5:00 PM).
This is the season of relentless sunshine and deep blue skies. Rainfall is almost non-existent in the south. Mainland cities like Athens can experience stifling heat, with temperatures often exceeding 35°C (95°F), exacerbated by the urban heat island effect. Locals typically observe a mid-day siesta to avoid the most scorching hours when the air feels heavy and still.
September feels like an extension of summer but with slightly shorter days and cooler evenings. By October, the first significant rains arrive, especially in the western Ionian islands. The sea remains warm enough for swimming well into October, a period locals call the "Little Summer of Saint Demetrius."
Winters are mild in the south but surprisingly cold in the north and the mountains. While the islands see frequent wind and rain, central and northern Greece (like Thessaloniki or the Pindus Mountains) regularly experience frost and heavy snowfall. Local life shifts indoors to the warmth of wood-burning stoves and hearty stews.
Spring is a brief but explosive transition. Landscapes turn vibrant green, and wildflowers blanket the archaeological sites. Temperatures are comfortable for physical activity (15°C to 25°C), though the sea remains too cold for most swimmers until late May.
The most famous weather phenomenon in Greece is the Meltemi (or Etesians). These are strong, dry northerly winds that sweep across the Aegean Sea from May to September, peaking in July and August.
Historically, Greece had very stable seasonal boundaries. However, recent decades have seen an increase in "extreme" events. Heatwaves that once lasted 2-3 days now occasionally persist for over a week, and the "Medicanes" (Mediterranean hurricanes)—rare, intense low-pressure systems—have become more frequent in the autumn, bringing heavy rainfall and gale-force winds to the southern mainland and islands.
Greek architecture and lifestyle are direct responses to the climate. The iconic white-washed houses of the islands reflect solar radiation to keep interiors cool. You will notice locals emerging in the evening (the volta or evening stroll) when the temperature drops, as daytime life in mid-summer is functionally suspended during the peak heat.