| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 9.6° | — | 75.2mm | 10.7 | 45 |
| February | 11.1° | — | 89mm | 12 | 48 |
| March | 14.9° | — | 112mm | 10.8 | 62 |
| April | 20.1° | — | 130.1mm | 10.4 | 79 |
| May | 25.1° | — | 124.8mm | 8.6 | 83 |
| June | 27.6° | — | 264.8mm | 12.5 | 73 |
| July | 31.2° | — | 340.8mm | 12.9 | 57 |
| August | 32.3° | — | 273.3mm | 11.8 | 55 |
| September | 28.3° | — | 209.6mm | 12 | 71 |
| October | 23.4° | — | 96.9mm | 7.8 | 84 |
| November | 17.6° | — | 87.8mm | 9.8 | 73 |
| December | 11.6° | — | 75.1mm | 12.6 | 48 |
January in Iizuka averages a daily high of 9.6°C. Expect roughly 10.7 wet days totalling 75.2mm. Demanding conditions — pack for it and plan indoor options.
February in Iizuka averages a daily high of 11.1°C. Expect roughly 12 wet days totalling 89mm. Demanding conditions — pack for it and plan indoor options.
March in Iizuka averages a daily high of 14.9°C. Expect roughly 10.8 wet days totalling 112mm. Generally workable, with some weather to plan around.
April in Iizuka averages a daily high of 20.1°C. Expect roughly 10.4 wet days totalling 130.1mm. Comfortable conditions for being outdoors all day.
May in Iizuka averages a daily high of 25.1°C. Expect roughly 8.6 wet days totalling 124.8mm. Comfortable conditions for being outdoors all day.
June in Iizuka averages a daily high of 27.6°C. Expect roughly 12.5 wet days totalling 264.8mm. Generally workable, with some weather to plan around.
July in Iizuka averages a daily high of 31.2°C. Expect roughly 12.9 wet days totalling 340.8mm. Generally workable, with some weather to plan around.
August in Iizuka averages a daily high of 32.3°C. Expect roughly 11.8 wet days totalling 273.3mm. Generally workable, with some weather to plan around.
September in Iizuka averages a daily high of 28.3°C. Expect roughly 12 wet days totalling 209.6mm. Generally workable, with some weather to plan around.
October in Iizuka averages a daily high of 23.4°C. Expect roughly 7.8 wet days totalling 96.9mm. Comfortable conditions for being outdoors all day.
November in Iizuka averages a daily high of 17.6°C. Expect roughly 9.8 wet days totalling 87.8mm. Generally workable, with some weather to plan around.
December in Iizuka averages a daily high of 11.6°C. Expect roughly 12.6 wet days totalling 75.1mm. 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. Iizuka peaks at 84.
Based on 30 years of records, April–May scores highest for comfort in Iizuka, balancing daytime temperature against rainfall.
August is the warmest, averaging a daily high of 32.3°C.
July is the wettest, averaging 340.8mm of rain across roughly 12.9 wet days.
January is the coolest month, with average daily highs around 9.6°C.