The dominant feature of Athens’ climate is alternation between prolonged hot and dry summers and mild, wetter winters with moderate rainfall. With an average of 433 millimetres of yearly precipitation, rainfall occurs largely between the months of October and April. July and August are the driest months when thunderstorms occur sparsely.

Furthermore, some coastal areas such as Piraeus in the Athens Riviera, have a hot semi-arid climate according to the climate atlas published by the Hellenic National Meteorological Service. However, places like Elliniko, which are classified as hot semi-arid (BSh) because of the low annual rainfall, have not recorded temperatures as high as other places in the city. This occurs due to the moderating influence of the sea, and lower levels of industrialisation compared to other regions of the city.

Due to the large area covered by Athens Metropolitan Area, there are notable climatic differences between parts of the urban conglomeration. The northern suburbs tend to be wetter and cooler in winter, whereas the southern suburbs are some of the driest locations in Greece and record very high minimum temperatures in summer.