Rainy season: There is no special rainy season
Avg. Temp. in Spring: max.: 9 – 18°C ( 49 - 64°F ); min: 1 - 9°C ( 34 - 49°F )
Avg. Temp. in Summer: max.: 21 – 23°C ( 70 - 74°F ); min: 12 - 13°C ( 53 - 55°F )
Avg. Temp. in Autumn: max.: 7 – 20°C ( 45 - 68°F); min: 2 - 10°C ( 36 – 50°F )
Avg. Temp. in Winter: max.: 3 – 4°C ( 38 - 39°F); min: 0 - 1°C ( 32 - 34°F )
Clothing/Shoes/Weather Gear: The best time of the year to visit Mainz is from June-August/September. If you're lucky, temperatures are about 25-30°C. But it can also rain during some days and get a bit colder, so be prepared. In fall it rains quite often, can be stormy and already pretty cold. In winter, especially in January/February it might snow for some days, but only if you're lucky. Temperatures should be about -5-5/8°C. In spring the weather's just crazy. In May it's often really hot during some days but then it gets colder again. For more information about the weather and which clothes to bring have a look at my Germany page!