Hennef Sieg, in North Rhine-Westphalia, Germany, is home to roughly 48,000 people in the Central European time zone at 50.8°N latitude.
In 2025, Hennef Sieg recorded an average annual temperature of 53°F. The hottest temperatures reached 100°F in July; the coolest were 22°F in December. Total precipitation for the year was 32 inches, with the wettest month being January. Snowfall for the year totaled approximately 3 inches.
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