The climate in Wiesbaden is classified as a temperate oceanic one. The summers are generally warm while the winters are quite cold. Rainfall is prevalent throughout the year, though it is neither too heavy nor present for longer durations. The average annual temperature ranges around 10 degree Celsius.
Summer: June to August is the summer season with August being the hottest month. Temperatures are usually around 18 – 20 degree Celsius. Rainfall is usually maximum during these months.
Fall: September - November undergo a drop in temperature to signal the incoming of winter months. Night time temperatures may plunge down significantly.
Winter: December to February are known for heavy snowfalls and the temperature can drop to -1 Degrees Celsius.
Spring: March to May is the spring season. Spring is known to arrive late in Germany and even in its midst, expect chilly days and snowy mornings. Once can witness the Nature blooming with all its glory.
Wiesbaden is one city that can probable be visited anytime of the year. If you want to witness snowfalls then head over to the city in the Winters, summers are great but can get a humid. But, undeniably Spring and Fall season is the best time to visit Wiesbaden. This is because the weather is too awesome to not be experienced. But be warned, as this is also the peak season and the city is very crowded.