| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 8.9° | 2.9° | 110.4mm | 17.6 | 34 |
| February | 9.9° | 2.7° | 71.3mm | 14.9 | 38 |
| March | 12.3° | 4.2° | 82.9mm | 16.8 | 45 |
| April | 15.2° | 6.2° | 58.3mm | 13.8 | 57 |
| May | 19° | 9.4° | 43.7mm | 10.6 | 76 |
| June | 21.9° | 12.2° | 34.4mm | 8.8 | 82 |
| July | 25.6° | 14.5° | 11.2mm | 3.8 | 92 |
| August | 25.6° | 14.7° | 20.2mm | 4.5 | 91 |
| September | 22° | 12° | 38.3mm | 8.6 | 83 |
| October | 16.2° | 8.2° | 84.9mm | 14.2 | 59 |
| November | 11.3° | 4.5° | 130.7mm | 16.8 | 42 |
| December | 8.3° | 2.6° | 108.4mm | 17.1 | 33 |
January in Renton averages a daily high of 8.9°C with nights around 2.9°C. Expect roughly 17.6 wet days totalling 110.4mm. A hard month to visit for comfort alone.
February in Renton averages a daily high of 9.9°C with nights around 2.7°C. Expect roughly 14.9 wet days totalling 71.3mm. Demanding conditions — pack for it and plan indoor options.
March in Renton averages a daily high of 12.3°C with nights around 4.2°C. Expect roughly 16.8 wet days totalling 82.9mm. Demanding conditions — pack for it and plan indoor options.
April in Renton averages a daily high of 15.2°C with nights around 6.2°C. Expect roughly 13.8 wet days totalling 58.3mm. Generally workable, with some weather to plan around.
May in Renton averages a daily high of 19°C with nights around 9.4°C. Expect roughly 10.6 wet days totalling 43.7mm. Comfortable conditions for being outdoors all day.
June in Renton averages a daily high of 21.9°C with nights around 12.2°C. Expect roughly 8.8 wet days totalling 34.4mm. Comfortable conditions for being outdoors all day.
July in Renton averages a daily high of 25.6°C with nights around 14.5°C. Expect roughly 3.8 wet days totalling 11.2mm. Comfortable conditions for being outdoors all day.
August in Renton averages a daily high of 25.6°C with nights around 14.7°C. Expect roughly 4.5 wet days totalling 20.2mm. Comfortable conditions for being outdoors all day.
September in Renton averages a daily high of 22°C with nights around 12°C. Expect roughly 8.6 wet days totalling 38.3mm. Comfortable conditions for being outdoors all day.
October in Renton averages a daily high of 16.2°C with nights around 8.2°C. Expect roughly 14.2 wet days totalling 84.9mm. Generally workable, with some weather to plan around.
November in Renton averages a daily high of 11.3°C with nights around 4.5°C. Expect roughly 16.8 wet days totalling 130.7mm. Demanding conditions — pack for it and plan indoor options.
December in Renton averages a daily high of 8.3°C with nights around 2.6°C. Expect roughly 17.1 wet days totalling 108.4mm. 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. Renton peaks at 92.
Based on 30 years of records, July–August scores highest for comfort in Renton, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 25.6°C.
November is the wettest, averaging 130.7mm of rain across roughly 16.8 wet days.
December is the coolest month, with average daily highs around 8.3°C.