| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 3.6° | -2.1° | 77.6mm | 16.9 | 11 |
| February | 5.8° | -1.8° | 65.3mm | 14.5 | 20 |
| March | 10° | -0.1° | 55.6mm | 14.1 | 37 |
| April | 15.2° | 2.6° | 46.2mm | 11.5 | 62 |
| May | 19.1° | 6.4° | 64.9mm | 12.6 | 72 |
| June | 22.9° | 9.7° | 59.9mm | 12.4 | 75 |
| July | 24.7° | 11.6° | 81.6mm | 14.1 | 72 |
| August | 24.4° | 11.1° | 73.5mm | 12.5 | 75 |
| September | 19.7° | 7.9° | 62.6mm | 11.6 | 76 |
| October | 13.9° | 4.9° | 66mm | 14.2 | 52 |
| November | 7.9° | 1.8° | 66.9mm | 15.5 | 31 |
| December | 4.2° | -1° | 79.1mm | 18 | 15 |
January in Siegen averages a daily high of 3.6°C with nights around -2.1°C. Expect roughly 16.9 wet days totalling 77.6mm. A hard month to visit for comfort alone.
February in Siegen averages a daily high of 5.8°C with nights around -1.8°C. Expect roughly 14.5 wet days totalling 65.3mm. A hard month to visit for comfort alone.
March in Siegen averages a daily high of 10°C with nights around -0.1°C. Expect roughly 14.1 wet days totalling 55.6mm. Demanding conditions — pack for it and plan indoor options.
April in Siegen averages a daily high of 15.2°C with nights around 2.6°C. Expect roughly 11.5 wet days totalling 46.2mm. Generally workable, with some weather to plan around.
May in Siegen averages a daily high of 19.1°C with nights around 6.4°C. Expect roughly 12.6 wet days totalling 64.9mm. Generally workable, with some weather to plan around.
June in Siegen averages a daily high of 22.9°C with nights around 9.7°C. Expect roughly 12.4 wet days totalling 59.9mm. Comfortable conditions for being outdoors all day.
July in Siegen averages a daily high of 24.7°C with nights around 11.6°C. Expect roughly 14.1 wet days totalling 81.6mm. Generally workable, with some weather to plan around.
August in Siegen averages a daily high of 24.4°C with nights around 11.1°C. Expect roughly 12.5 wet days totalling 73.5mm. Comfortable conditions for being outdoors all day.
September in Siegen averages a daily high of 19.7°C with nights around 7.9°C. Expect roughly 11.6 wet days totalling 62.6mm. Comfortable conditions for being outdoors all day.
October in Siegen averages a daily high of 13.9°C with nights around 4.9°C. Expect roughly 14.2 wet days totalling 66mm. Demanding conditions — pack for it and plan indoor options.
November in Siegen averages a daily high of 7.9°C with nights around 1.8°C. Expect roughly 15.5 wet days totalling 66.9mm. A hard month to visit for comfort alone.
December in Siegen averages a daily high of 4.2°C with nights around -1°C. Expect roughly 18 wet days totalling 79.1mm. A hard month to visit for comfort alone.
Each month scores out of 100. It starts at 100 and loses points for daytime highs outside a 20–27°C band, for wet days, and for nights below 2°C. Nothing else is weighted in — no crowd data, no prices, no opinion. Siegen peaks at 76.
Based on 30 years of records, May–September scores highest for comfort in Siegen, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 24.7°C.
July is the wettest, averaging 81.6mm of rain across roughly 14.1 wet days.
January is the coolest month, with average daily highs around 3.6°C.