Summers in Frankfurt can get very warm, when compared to the rest of the country. Between the years 1981 and 2010 there have been 52 days in Frankfurt with a maximum temperature over 25 °C and 13 days with a maximum over 30 °C on average per year.

Being an urban heat island, Frankfurt is sometimes affected by tropical nights, where the temperature does not drop under 20 °C between May and September. This occurs because the density of the city causes it to store all the heat.

The growing season is longer when compared to the rest of Germany, thus resulting in an early arrival of springtime in the region.

Winters in Frankfurt are generally mild or at least not freezing with a small possibility of snow, especially in January and February but dark and often overcast. Frankfurt is, on average, covered with snow only for around 10 to 20 days per year.

The temperatures fell at about 70 days under 0 °C and daily maximum has stayed under 0 °C for about 13 days on average per year between 1981 and 2010. Some days with lows under −10 °C can occur more often here than at the coasts of Northern Germany, but not that frequently like in Bavaria or the eastern parts of Germany.