| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 8.1° | 2.1° | 60.4mm | 14.6 | 33 |
| February | 9.2° | 2.6° | 50.7mm | 13 | 39 |
| March | 11.6° | 3.6° | 46mm | 12.4 | 48 |
| April | 14.7° | 5.1° | 46.1mm | 11.2 | 61 |
| May | 17.9° | 8.2° | 58.3mm | 12.2 | 69 |
| June | 21.1° | 11.2° | 51.1mm | 10.9 | 78 |
| July | 23.3° | 13.1° | 52.1mm | 10.8 | 78 |
| August | 22.7° | 13.1° | 57.7mm | 11.6 | 77 |
| September | 19.8° | 10.8° | 53.8mm | 11.1 | 77 |
| October | 15.5° | 8.3° | 76.7mm | 14.3 | 57 |
| November | 11° | 4.7° | 72.4mm | 15.8 | 41 |
| December | 8.5° | 2.5° | 68.5mm | 15.4 | 33 |
January in Bletchley averages a daily high of 8.1°C with nights around 2.1°C. Expect roughly 14.6 wet days totalling 60.4mm. A hard month to visit for comfort alone.
February in Bletchley averages a daily high of 9.2°C with nights around 2.6°C. Expect roughly 13 wet days totalling 50.7mm. Demanding conditions — pack for it and plan indoor options.
March in Bletchley averages a daily high of 11.6°C with nights around 3.6°C. Expect roughly 12.4 wet days totalling 46mm. Demanding conditions — pack for it and plan indoor options.
April in Bletchley averages a daily high of 14.7°C with nights around 5.1°C. Expect roughly 11.2 wet days totalling 46.1mm. Generally workable, with some weather to plan around.
May in Bletchley averages a daily high of 17.9°C with nights around 8.2°C. Expect roughly 12.2 wet days totalling 58.3mm. Generally workable, with some weather to plan around.
June in Bletchley averages a daily high of 21.1°C with nights around 11.2°C. Expect roughly 10.9 wet days totalling 51.1mm. Comfortable conditions for being outdoors all day.
July in Bletchley averages a daily high of 23.3°C with nights around 13.1°C. Expect roughly 10.8 wet days totalling 52.1mm. Comfortable conditions for being outdoors all day.
August in Bletchley averages a daily high of 22.7°C with nights around 13.1°C. Expect roughly 11.6 wet days totalling 57.7mm. Comfortable conditions for being outdoors all day.
September in Bletchley averages a daily high of 19.8°C with nights around 10.8°C. Expect roughly 11.1 wet days totalling 53.8mm. Comfortable conditions for being outdoors all day.
October in Bletchley averages a daily high of 15.5°C with nights around 8.3°C. Expect roughly 14.3 wet days totalling 76.7mm. Generally workable, with some weather to plan around.
November in Bletchley averages a daily high of 11°C with nights around 4.7°C. Expect roughly 15.8 wet days totalling 72.4mm. Demanding conditions — pack for it and plan indoor options.
December in Bletchley averages a daily high of 8.5°C with nights around 2.5°C. Expect roughly 15.4 wet days totalling 68.5mm. 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. Bletchley peaks at 78.
Based on 30 years of records, June–September scores highest for comfort in Bletchley, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 23.3°C.
October is the wettest, averaging 76.7mm of rain across roughly 14.3 wet days.
January is the coolest month, with average daily highs around 8.1°C.