| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 9.2° | 3.9° | 108.5mm | 17.9 | 35 |
| February | 9.6° | 4.1° | 89.9mm | 16.4 | 37 |
| March | 11.1° | 4.8° | 82.1mm | 14.9 | 42 |
| April | 13.5° | 6.3° | 65.2mm | 12.9 | 53 |
| May | 16.3° | 8.7° | 62mm | 12.6 | 63 |
| June | 18.9° | 11.5° | 61.7mm | 11.9 | 73 |
| July | 20.5° | 13.2° | 65.9mm | 12.1 | 76 |
| August | 20.5° | 13.4° | 76.6mm | 13.6 | 73 |
| September | 18.7° | 11.8° | 70.4mm | 12.6 | 71 |
| October | 15.5° | 9.9° | 115.4mm | 18.1 | 56 |
| November | 12° | 6.6° | 120mm | 19.2 | 44 |
| December | 9.8° | 4.7° | 124.4mm | 18.6 | 37 |
January in Plymouth averages a daily high of 9.2°C with nights around 3.9°C. Expect roughly 17.9 wet days totalling 108.5mm. Demanding conditions — pack for it and plan indoor options.
February in Plymouth averages a daily high of 9.6°C with nights around 4.1°C. Expect roughly 16.4 wet days totalling 89.9mm. Demanding conditions — pack for it and plan indoor options.
March in Plymouth averages a daily high of 11.1°C with nights around 4.8°C. Expect roughly 14.9 wet days totalling 82.1mm. Demanding conditions — pack for it and plan indoor options.
April in Plymouth averages a daily high of 13.5°C with nights around 6.3°C. Expect roughly 12.9 wet days totalling 65.2mm. Demanding conditions — pack for it and plan indoor options.
May in Plymouth averages a daily high of 16.3°C with nights around 8.7°C. Expect roughly 12.6 wet days totalling 62mm. Generally workable, with some weather to plan around.
June in Plymouth averages a daily high of 18.9°C with nights around 11.5°C. Expect roughly 11.9 wet days totalling 61.7mm. Generally workable, with some weather to plan around.
July in Plymouth averages a daily high of 20.5°C with nights around 13.2°C. Expect roughly 12.1 wet days totalling 65.9mm. Comfortable conditions for being outdoors all day.
August in Plymouth averages a daily high of 20.5°C with nights around 13.4°C. Expect roughly 13.6 wet days totalling 76.6mm. Generally workable, with some weather to plan around.
September in Plymouth averages a daily high of 18.7°C with nights around 11.8°C. Expect roughly 12.6 wet days totalling 70.4mm. Generally workable, with some weather to plan around.
October in Plymouth averages a daily high of 15.5°C with nights around 9.9°C. Expect roughly 18.1 wet days totalling 115.4mm. Generally workable, with some weather to plan around.
November in Plymouth averages a daily high of 12°C with nights around 6.6°C. Expect roughly 19.2 wet days totalling 120mm. Demanding conditions — pack for it and plan indoor options.
December in Plymouth averages a daily high of 9.8°C with nights around 4.7°C. Expect roughly 18.6 wet days totalling 124.4mm. Demanding conditions — pack for it and plan indoor options.
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. Plymouth peaks at 76.
Based on 30 years of records, June–September scores highest for comfort in Plymouth, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 20.5°C.
December is the wettest, averaging 124.4mm of rain across roughly 18.6 wet days.
January is the coolest month, with average daily highs around 9.2°C.