| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 9.4° | — | 32.7mm | 5.6 | 55 |
| February | 10.2° | — | 58.5mm | 7.9 | 53 |
| March | 13.9° | — | 96.2mm | 10.1 | 60 |
| April | 19° | — | 109.4mm | 10 | 77 |
| May | 23.8° | — | 142.6mm | 9.2 | 82 |
| June | 26.9° | — | 187.6mm | 11.5 | 77 |
| July | 30.7° | — | 194.3mm | 11 | 63 |
| August | 32.4° | — | 121.6mm | 7.6 | 63 |
| September | 28.8° | — | 159.7mm | 10.4 | 72 |
| October | 23.3° | — | 113.6mm | 8.5 | 83 |
| November | 17.6° | — | 69.7mm | 6.9 | 79 |
| December | 12.1° | — | 51mm | 6.8 | 61 |
January in Ashiya averages a daily high of 9.4°C. Expect roughly 5.6 wet days totalling 32.7mm. Generally workable, with some weather to plan around.
February in Ashiya averages a daily high of 10.2°C. Expect roughly 7.9 wet days totalling 58.5mm. Demanding conditions — pack for it and plan indoor options.
March in Ashiya averages a daily high of 13.9°C. Expect roughly 10.1 wet days totalling 96.2mm. Generally workable, with some weather to plan around.
April in Ashiya averages a daily high of 19°C. Expect roughly 10 wet days totalling 109.4mm. Comfortable conditions for being outdoors all day.
May in Ashiya averages a daily high of 23.8°C. Expect roughly 9.2 wet days totalling 142.6mm. Comfortable conditions for being outdoors all day.
June in Ashiya averages a daily high of 26.9°C. Expect roughly 11.5 wet days totalling 187.6mm. Comfortable conditions for being outdoors all day.
July in Ashiya averages a daily high of 30.7°C. Expect roughly 11 wet days totalling 194.3mm. Generally workable, with some weather to plan around.
August in Ashiya averages a daily high of 32.4°C. Expect roughly 7.6 wet days totalling 121.6mm. Generally workable, with some weather to plan around.
September in Ashiya averages a daily high of 28.8°C. Expect roughly 10.4 wet days totalling 159.7mm. Generally workable, with some weather to plan around.
October in Ashiya averages a daily high of 23.3°C. Expect roughly 8.5 wet days totalling 113.6mm. Comfortable conditions for being outdoors all day.
November in Ashiya averages a daily high of 17.6°C. Expect roughly 6.9 wet days totalling 69.7mm. Comfortable conditions for being outdoors all day.
December in Ashiya averages a daily high of 12.1°C. Expect roughly 6.8 wet days totalling 51mm. Generally workable, with some weather to plan around.
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. Ashiya peaks at 83.
Based on 30 years of records, April–June scores highest for comfort in Ashiya, balancing daytime temperature against rainfall.
August is the warmest, averaging a daily high of 32.4°C.
July is the wettest, averaging 194.3mm of rain across roughly 11 wet days.
January is the coolest month, with average daily highs around 9.4°C.