Generally the liquid is water and the fluid above the liquid is air. The molecules within the liquid attract each other and at the interface there are more attractive forces towards the bulk of the liquid than there are towards the adjacent gas molecules. The molecular forces tend to pull into the fluid bulk.
Weather lowdown. Despite the fact that the month of September in Athens can produce summer-like temperatures, the weather starts to cool off significantly in October, and especially at night. The average temperature this month is 19Â°C (66Â°F), while the average low is 15Â°C (59Â°C), and the average high is 23Â°C (73Â°F).
Athens: Annual Weather Averages. August is the hottest month in Athens with an average temperature of 29Â°C (84Â°F) and the coldest is January at 10Â°C (50Â°F) with the most daily sunshine hours at 12 in July. The wettest month is December with an average of 97.6mm of rain. The best month to swim in the sea is in August when the average sea temperature is 25 Â°C (77 Â°F). Average Temperature: Athens