| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 7.3° | 1.7° | 97.4mm | 19 | 29 |
| February | 8.1° | 2.2° | 95.4mm | 18.2 | 32 |
| March | 9.7° | 2.9° | 70.6mm | 15.4 | 37 |
| April | 12.3° | 4.2° | 54.3mm | 13.5 | 48 |
| May | 15.3° | 6.8° | 57.1mm | 14.2 | 57 |
| June | 17.5° | 9.6° | 66.7mm | 13.8 | 64 |
| July | 18.8° | 11.4° | 84.9mm | 16.3 | 66 |
| August | 18.8° | 11.4° | 89.2mm | 16.5 | 66 |
| September | 16.7° | 9.7° | 83.7mm | 16 | 59 |
| October | 13.4° | 7.1° | 115.1mm | 19.9 | 49 |
| November | 10° | 3.9° | 107.8mm | 19.3 | 38 |
| December | 7.8° | 1.6° | 111.2mm | 20.2 | 30 |
January in Hamilton averages a daily high of 7.3°C with nights around 1.7°C. Expect roughly 19 wet days totalling 97.4mm. A hard month to visit for comfort alone.
February in Hamilton averages a daily high of 8.1°C with nights around 2.2°C. Expect roughly 18.2 wet days totalling 95.4mm. A hard month to visit for comfort alone.
March in Hamilton averages a daily high of 9.7°C with nights around 2.9°C. Expect roughly 15.4 wet days totalling 70.6mm. Demanding conditions — pack for it and plan indoor options.
April in Hamilton averages a daily high of 12.3°C with nights around 4.2°C. Expect roughly 13.5 wet days totalling 54.3mm. Demanding conditions — pack for it and plan indoor options.
May in Hamilton averages a daily high of 15.3°C with nights around 6.8°C. Expect roughly 14.2 wet days totalling 57.1mm. Generally workable, with some weather to plan around.
June in Hamilton averages a daily high of 17.5°C with nights around 9.6°C. Expect roughly 13.8 wet days totalling 66.7mm. Generally workable, with some weather to plan around.
July in Hamilton averages a daily high of 18.8°C with nights around 11.4°C. Expect roughly 16.3 wet days totalling 84.9mm. Generally workable, with some weather to plan around.
August in Hamilton averages a daily high of 18.8°C with nights around 11.4°C. Expect roughly 16.5 wet days totalling 89.2mm. Generally workable, with some weather to plan around.
September in Hamilton averages a daily high of 16.7°C with nights around 9.7°C. Expect roughly 16 wet days totalling 83.7mm. Generally workable, with some weather to plan around.
October in Hamilton averages a daily high of 13.4°C with nights around 7.1°C. Expect roughly 19.9 wet days totalling 115.1mm. Demanding conditions — pack for it and plan indoor options.
November in Hamilton averages a daily high of 10°C with nights around 3.9°C. Expect roughly 19.3 wet days totalling 107.8mm. Demanding conditions — pack for it and plan indoor options.
December in Hamilton averages a daily high of 7.8°C with nights around 1.6°C. Expect roughly 20.2 wet days totalling 111.2mm. 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. Hamilton peaks at 66.
Based on 30 years of records, June–September scores highest for comfort in Hamilton, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 18.8°C.
October is the wettest, averaging 115.1mm of rain across roughly 19.9 wet days.
January is the coolest month, with average daily highs around 7.3°C.