| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 7.1° | 1.3° | 53.2mm | 14.9 | 28 |
| February | 8.2° | 1.6° | 45.6mm | 12.6 | 36 |
| March | 10.2° | 2.5° | 40.1mm | 12.3 | 44 |
| April | 12.7° | 3.9° | 46.9mm | 11.1 | 54 |
| May | 15.7° | 6.7° | 46.1mm | 12.9 | 60 |
| June | 18.3° | 9.4° | 60.3mm | 11.9 | 71 |
| July | 20.3° | 11.5° | 65.9mm | 13.9 | 72 |
| August | 20° | 11.5° | 60.4mm | 13.5 | 73 |
| September | 17.6° | 9.5° | 53.2mm | 11.9 | 69 |
| October | 13.8° | 6.8° | 69.4mm | 15.8 | 50 |
| November | 9.8° | 3.7° | 73.9mm | 15.5 | 37 |
| December | 7.5° | 1.6° | 60.4mm | 15.6 | 29 |
January in Washington averages a daily high of 7.1°C with nights around 1.3°C. Expect roughly 14.9 wet days totalling 53.2mm. A hard month to visit for comfort alone.
February in Washington averages a daily high of 8.2°C with nights around 1.6°C. Expect roughly 12.6 wet days totalling 45.6mm. Demanding conditions — pack for it and plan indoor options.
March in Washington averages a daily high of 10.2°C with nights around 2.5°C. Expect roughly 12.3 wet days totalling 40.1mm. Demanding conditions — pack for it and plan indoor options.
April in Washington averages a daily high of 12.7°C with nights around 3.9°C. Expect roughly 11.1 wet days totalling 46.9mm. Demanding conditions — pack for it and plan indoor options.
May in Washington averages a daily high of 15.7°C with nights around 6.7°C. Expect roughly 12.9 wet days totalling 46.1mm. Generally workable, with some weather to plan around.
June in Washington averages a daily high of 18.3°C with nights around 9.4°C. Expect roughly 11.9 wet days totalling 60.3mm. Generally workable, with some weather to plan around.
July in Washington averages a daily high of 20.3°C with nights around 11.5°C. Expect roughly 13.9 wet days totalling 65.9mm. Generally workable, with some weather to plan around.
August in Washington averages a daily high of 20°C with nights around 11.5°C. Expect roughly 13.5 wet days totalling 60.4mm. Generally workable, with some weather to plan around.
September in Washington averages a daily high of 17.6°C with nights around 9.5°C. Expect roughly 11.9 wet days totalling 53.2mm. Generally workable, with some weather to plan around.
October in Washington averages a daily high of 13.8°C with nights around 6.8°C. Expect roughly 15.8 wet days totalling 69.4mm. Demanding conditions — pack for it and plan indoor options.
November in Washington averages a daily high of 9.8°C with nights around 3.7°C. Expect roughly 15.5 wet days totalling 73.9mm. Demanding conditions — pack for it and plan indoor options.
December in Washington averages a daily high of 7.5°C with nights around 1.6°C. Expect roughly 15.6 wet days totalling 60.4mm. 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. Washington peaks at 73.
Based on 30 years of records, June–September scores highest for comfort in Washington, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 20.3°C.
November is the wettest, averaging 73.9mm of rain across roughly 15.5 wet days.
January is the coolest month, with average daily highs around 7.1°C.