| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 3.6° | -1.1° | 66.1mm | 13 | 17 |
| February | 5.8° | -0.6° | 61.6mm | 11.7 | 27 |
| March | 10.4° | 2° | 71.6mm | 12.9 | 43 |
| April | 14.9° | 5.2° | 79.3mm | 11.9 | 60 |
| May | 18.8° | 9.2° | 127.8mm | 15 | 66 |
| June | 22.9° | 13° | 124.6mm | 13.8 | 72 |
| July | 24.4° | 14.6° | 127.9mm | 14.9 | 70 |
| August | 23.9° | 14.5° | 120mm | 13.6 | 73 |
| September | 19.3° | 10.8° | 88.6mm | 11.9 | 74 |
| October | 14.3° | 7.5° | 81.4mm | 12.3 | 57 |
| November | 7.8° | 2.7° | 75.8mm | 12.7 | 36 |
| December | 4.1° | -0.3° | 84.5mm | 14.3 | 17 |
January in Winterthur averages a daily high of 3.6°C with nights around -1.1°C. Expect roughly 13 wet days totalling 66.1mm. A hard month to visit for comfort alone.
February in Winterthur averages a daily high of 5.8°C with nights around -0.6°C. Expect roughly 11.7 wet days totalling 61.6mm. A hard month to visit for comfort alone.
March in Winterthur averages a daily high of 10.4°C with nights around 2°C. Expect roughly 12.9 wet days totalling 71.6mm. Demanding conditions — pack for it and plan indoor options.
April in Winterthur averages a daily high of 14.9°C with nights around 5.2°C. Expect roughly 11.9 wet days totalling 79.3mm. Generally workable, with some weather to plan around.
May in Winterthur averages a daily high of 18.8°C with nights around 9.2°C. Expect roughly 15 wet days totalling 127.8mm. Generally workable, with some weather to plan around.
June in Winterthur averages a daily high of 22.9°C with nights around 13°C. Expect roughly 13.8 wet days totalling 124.6mm. Generally workable, with some weather to plan around.
July in Winterthur averages a daily high of 24.4°C with nights around 14.6°C. Expect roughly 14.9 wet days totalling 127.9mm. Generally workable, with some weather to plan around.
August in Winterthur averages a daily high of 23.9°C with nights around 14.5°C. Expect roughly 13.6 wet days totalling 120mm. Generally workable, with some weather to plan around.
September in Winterthur averages a daily high of 19.3°C with nights around 10.8°C. Expect roughly 11.9 wet days totalling 88.6mm. Generally workable, with some weather to plan around.
October in Winterthur averages a daily high of 14.3°C with nights around 7.5°C. Expect roughly 12.3 wet days totalling 81.4mm. Generally workable, with some weather to plan around.
November in Winterthur averages a daily high of 7.8°C with nights around 2.7°C. Expect roughly 12.7 wet days totalling 75.8mm. Demanding conditions — pack for it and plan indoor options.
December in Winterthur averages a daily high of 4.1°C with nights around -0.3°C. Expect roughly 14.3 wet days totalling 84.5mm. 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. Winterthur peaks at 74.
Based on 30 years of records, May–September scores highest for comfort in Winterthur, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 24.4°C.
July is the wettest, averaging 127.9mm of rain across roughly 14.9 wet days.
January is the coolest month, with average daily highs around 3.6°C.