| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 2.8° | -5.7° | 81.9mm | 12 | 9 |
| February | 5.2° | -4° | 64.7mm | 10.1 | 23 |
| March | 10.9° | 0° | 93.1mm | 11.2 | 45 |
| April | 18.4° | 6° | 110.3mm | 12.6 | 70 |
| May | 24.1° | 12.5° | 113.3mm | 13.5 | 73 |
| June | 29° | 18° | 119.9mm | 12.3 | 67 |
| July | 30.6° | 19.8° | 109.7mm | 10.3 | 65 |
| August | 30.4° | 18.8° | 79.2mm | 8.1 | 70 |
| September | 26.5° | 14.3° | 76.8mm | 8 | 84 |
| October | 19.3° | 7.3° | 75.5mm | 9.2 | 79 |
| November | 11.5° | 1.3° | 72.5mm | 9.1 | 54 |
| December | 4.9° | -3.3° | 80.5mm | 11.3 | 21 |
January in Dayton averages a daily high of 2.8°C with nights around -5.7°C. Expect roughly 12 wet days totalling 81.9mm. A hard month to visit for comfort alone.
February in Dayton averages a daily high of 5.2°C with nights around -4°C. Expect roughly 10.1 wet days totalling 64.7mm. A hard month to visit for comfort alone.
March in Dayton averages a daily high of 10.9°C with nights around 0°C. Expect roughly 11.2 wet days totalling 93.1mm. Demanding conditions — pack for it and plan indoor options.
April in Dayton averages a daily high of 18.4°C with nights around 6°C. Expect roughly 12.6 wet days totalling 110.3mm. Generally workable, with some weather to plan around.
May in Dayton averages a daily high of 24.1°C with nights around 12.5°C. Expect roughly 13.5 wet days totalling 113.3mm. Generally workable, with some weather to plan around.
June in Dayton averages a daily high of 29°C with nights around 18°C. Expect roughly 12.3 wet days totalling 119.9mm. Generally workable, with some weather to plan around.
July in Dayton averages a daily high of 30.6°C with nights around 19.8°C. Expect roughly 10.3 wet days totalling 109.7mm. Generally workable, with some weather to plan around.
August in Dayton averages a daily high of 30.4°C with nights around 18.8°C. Expect roughly 8.1 wet days totalling 79.2mm. Generally workable, with some weather to plan around.
September in Dayton averages a daily high of 26.5°C with nights around 14.3°C. Expect roughly 8 wet days totalling 76.8mm. Comfortable conditions for being outdoors all day.
October in Dayton averages a daily high of 19.3°C with nights around 7.3°C. Expect roughly 9.2 wet days totalling 75.5mm. Comfortable conditions for being outdoors all day.
November in Dayton averages a daily high of 11.5°C with nights around 1.3°C. Expect roughly 9.1 wet days totalling 72.5mm. Demanding conditions — pack for it and plan indoor options.
December in Dayton averages a daily high of 4.9°C with nights around -3.3°C. Expect roughly 11.3 wet days totalling 80.5mm. 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. Dayton peaks at 84.
Based on 30 years of records, September–October scores highest for comfort in Dayton, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 30.6°C.
June is the wettest, averaging 119.9mm of rain across roughly 12.3 wet days.
January is the coolest month, with average daily highs around 2.8°C.