The atmosphere is always warm, but fierce heat waves (temperatures above 38 °C) are not very common, since the prevailing Etesian winds (“Meltemia”) blow from northern directions and pleasantly moderate the conditions. Intervals of sunny days are frequent during the windy and rainy winter as well.

Snow and frost are rare near the coast, with very few exceptions, like the snowstorm on 13 February 2004, when 25–75 cm of snow accumulated in the urban area, causing general chaos. The last significant snowstorm happened on 8 January 2017 when the whole city and the old harbour was blanketed by snow.

However, such cold days can be followed by much warmer and sunny weather. Minor early heat waves can occur in March or April, during a Saharan dust event[citation needed], whose main feature is the strong and hot katabatic wind from the south, which is a type of Sirokos (σιρόκος) and is called “Livas” (i.e. the wind from Libya) by the Greeks.

The adjacent chart is based on data recorded during 1958–1997. The absolute maximum temperature recorded during this period was 42.5 °C, while the absolute minimum recorded was 0 °C.

However, the record minimum was broken on 13 February 2004 when the temperature dropped to −1 °C and the record maximum was broken on 1 July 2021 when the temperature passed 44 °C.