| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 3.4° | — | 79.5mm | 18 | 17 |
| February | 4.6° | — | 68.1mm | 13.7 | 23 |
| March | 9.8° | — | 66.5mm | 12.4 | 43 |
| April | 16.8° | — | 73.8mm | 11.3 | 67 |
| May | 23.1° | — | 71.2mm | 9.5 | 81 |
| June | 26.2° | — | 96.6mm | 10.4 | 79 |
| July | 29.6° | — | 199.8mm | 15 | 60 |
| August | 30.8° | — | 142.1mm | 11.5 | 62 |
| September | 26° | — | 125.7mm | 10.6 | 79 |
| October | 19.6° | — | 101.2mm | 10.7 | 77 |
| November | 12.8° | — | 76.7mm | 12.7 | 52 |
| December | 6.2° | — | 107.9mm | 17.9 | 26 |
January in Yonezawa averages a daily high of 3.4°C. Expect roughly 18 wet days totalling 79.5mm. A hard month to visit for comfort alone.
February in Yonezawa averages a daily high of 4.6°C. Expect roughly 13.7 wet days totalling 68.1mm. A hard month to visit for comfort alone.
March in Yonezawa averages a daily high of 9.8°C. Expect roughly 12.4 wet days totalling 66.5mm. Demanding conditions — pack for it and plan indoor options.
April in Yonezawa averages a daily high of 16.8°C. Expect roughly 11.3 wet days totalling 73.8mm. Generally workable, with some weather to plan around.
May in Yonezawa averages a daily high of 23.1°C. Expect roughly 9.5 wet days totalling 71.2mm. Comfortable conditions for being outdoors all day.
June in Yonezawa averages a daily high of 26.2°C. Expect roughly 10.4 wet days totalling 96.6mm. Comfortable conditions for being outdoors all day.
July in Yonezawa averages a daily high of 29.6°C. Expect roughly 15 wet days totalling 199.8mm. Generally workable, with some weather to plan around.
August in Yonezawa averages a daily high of 30.8°C. Expect roughly 11.5 wet days totalling 142.1mm. Generally workable, with some weather to plan around.
September in Yonezawa averages a daily high of 26°C. Expect roughly 10.6 wet days totalling 125.7mm. Comfortable conditions for being outdoors all day.
October in Yonezawa averages a daily high of 19.6°C. Expect roughly 10.7 wet days totalling 101.2mm. Comfortable conditions for being outdoors all day.
November in Yonezawa averages a daily high of 12.8°C. Expect roughly 12.7 wet days totalling 76.7mm. Demanding conditions — pack for it and plan indoor options.
December in Yonezawa averages a daily high of 6.2°C. Expect roughly 17.9 wet days totalling 107.9mm. 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. Yonezawa peaks at 81.
Based on 30 years of records, May–June scores highest for comfort in Yonezawa, balancing daytime temperature against rainfall.
August is the warmest, averaging a daily high of 30.8°C.
July is the wettest, averaging 199.8mm of rain across roughly 15 wet days.
January is the coolest month, with average daily highs around 3.4°C.