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Koblenz sits where the Rhine and Moselle rivers meet, in a sheltered valley that counts as one of the warmest corners of Germany. The city averages 24°C (75°F) highs in July and 4°C (39°F) in January, with about 650 mm of rain spread across the year. Rain is the one thing to plan around: no month is fully dry, but February is the driest at around 40 mm. Use this page together with our best time to visit Koblenz guide to pick your dates.
Koblenz Weather by Month: What to Expect
Koblenz has a mild oceanic climate with a light continental nudge, thanks to its Rhine valley position around 65 m above sea level. Annual rainfall averages about 649 mm at the city’s official station, and the sunniest months are June and July with roughly 7.4 hours of sun a day. Winter highs rarely stay below 0°C for long, but valley fog can settle in between November and February, cutting sunshine to under 2 hours a day in December. The table below lists the monthly averages, and you can pair them with our things to do in Koblenz guide to mix indoor and outdoor days.
| Month | Avg High | Avg Low | Rain (mm) | Sun (hrs) |
|---|---|---|---|---|
| January | 4°C (39°F) | 0°C | 52 | 1.5 |
| February | 6°C (43°F) | 0°C | 40 | 2.8 |
| March | 10°C (50°F) | 3°C | 46 | 4.1 |
| April | 14°C (57°F) | 5°C | 44 | 5.6 |
| May | 19°C (66°F) | 9°C | 58 | 6.9 |
| June | 22°C (72°F) | 12°C | 65 | 7.2 |
| July | 24°C (75°F) | 14°C | 62 | 7.4 |
| August | 24°C (75°F) | 14°C | 60 | 6.8 |
| September | 20°C (68°F) | 11°C | 52 | 5.1 |
| October | 14°C (57°F) | 7°C | 55 | 3.4 |
| November | 8°C (46°F) | 3°C | 55 | 1.8 |
| December | 5°C (41°F) | 1°C | 60 | 1.3 |
Koblenz Weather by Month: Winter (December to February)
December brings the year’s highest rainfall at about 60 mm and the fewest sunshine hours, around 1.3 a day, which makes the Old Town Christmas markets the main outdoor draw. January averages 4°C (39°F) by day and 0°C (32°F) at night, with 52 mm of rain and light frost on roughly 10 mornings. February is the driest month at about 40 mm, with highs edging up to 6°C (43°F). Snow does fall, but it settles in the valley only a few days each winter; the Hunsrück hills west of town get more. Pack a waterproof jacket rather than heavy snow gear, and check our Koblenz events and festivals page for the Carnival dates that usually fall in February.
Koblenz Weather by Month: Spring (March to May)
March climbs to 10°C (50°F) highs and shifts things back outdoors, with 46 mm of rain. April reaches 14°C (57°F) and May 19°C (66°F), making May the first reliably warm month for the fortress cable car and the river terraces. Rainfall stays moderate through spring at 44 to 58 mm a month. The Rhine promenade and the Stolzenfels Castle grounds come alive by late April, and visitor numbers climb fast, so reserve through our where to stay in Koblenz guide early if you travel in May.
Koblenz Weather by Month: Summer (June to August)
Summer is the warmest and busiest season. July and August both average 24°C (75°F) by day and 14°C (57°F) at night, and afternoon thunderstorms push June and July rain to 65 mm and 62 mm respectively. Expect around 7.4 hours of sunshine a day in July, the most of the year. This is peak river cruise season on the Rhine and Moselle, and the Rhine in Flames fireworks night in August draws the biggest crowds of the year. Evenings stay mild enough for dinner on the Deutsches Eck promenade, and our Koblenz neighborhoods guide covers the best districts for warm nights out.
Koblenz Weather by Month: Autumn (September to November)
September is still warm at 20°C (68°F) with 52 mm of rain, and it is one of the best months to visit: warm days, thinner crowds and the Moselle vineyard harvest. October cools to 14°C (57°F) with 55 mm, and the autumn colour along the Rhine gorge peaks from mid to late October. November drops to 8°C (46°F) and turns grey and foggy, with 55 mm of rain. If you want the castles without the summer queues, aim for September, and see our Koblenz travel tips page for what to pack. For the full seasonal picture, start with the Koblenz guide.
