Overview: KoblenzKoblenz (Germany) is a place with a mild climate. The day temperatures range from 5 °C (41 °F) in January to 25 °C (76 °F) in July. The highest night temperatures could be experienced in July with 14 °C (58 °F), the lowest in February with 0 °C (32 °F). The driest month is September with just 11 days of rain, on the contrary, the month when it rains the most is December with 14 days of rain.