| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 7.1° | -1° | 73mm | 9.7 | 35 |
| February | 9.1° | 0° | 67.3mm | 9.7 | 43 |
| March | 13.9° | 3.7° | 80.4mm | 10.3 | 60 |
| April | 19.8° | 8.9° | 83.6mm | 10.7 | 78 |
| May | 24.4° | 14.3° | 105.1mm | 12 | 76 |
| June | 29.3° | 19.5° | 110.7mm | 10.8 | 69 |
| July | 31.7° | 22.3° | 117.5mm | 10.5 | 60 |
| August | 30.9° | 21.6° | 88.5mm | 9 | 66 |
| September | 27° | 17.8° | 98.7mm | 8.7 | 83 |
| October | 20.8° | 11.3° | 93.2mm | 8.2 | 84 |
| November | 14.4° | 5.2° | 71.6mm | 8.1 | 66 |
| December | 9.3° | 1.3° | 86mm | 9.8 | 45 |
January in Washington averages a daily high of 7.1°C with nights around -1°C. Expect roughly 9.7 wet days totalling 73mm. Demanding conditions — pack for it and plan indoor options.
February in Washington averages a daily high of 9.1°C with nights around 0°C. Expect roughly 9.7 wet days totalling 67.3mm. Demanding conditions — pack for it and plan indoor options.
March in Washington averages a daily high of 13.9°C with nights around 3.7°C. Expect roughly 10.3 wet days totalling 80.4mm. Generally workable, with some weather to plan around.
April in Washington averages a daily high of 19.8°C with nights around 8.9°C. Expect roughly 10.7 wet days totalling 83.6mm. Comfortable conditions for being outdoors all day.
May in Washington averages a daily high of 24.4°C with nights around 14.3°C. Expect roughly 12 wet days totalling 105.1mm. Comfortable conditions for being outdoors all day.
June in Washington averages a daily high of 29.3°C with nights around 19.5°C. Expect roughly 10.8 wet days totalling 110.7mm. Generally workable, with some weather to plan around.
July in Washington averages a daily high of 31.7°C with nights around 22.3°C. Expect roughly 10.5 wet days totalling 117.5mm. Generally workable, with some weather to plan around.
August in Washington averages a daily high of 30.9°C with nights around 21.6°C. Expect roughly 9 wet days totalling 88.5mm. Generally workable, with some weather to plan around.
September in Washington averages a daily high of 27°C with nights around 17.8°C. Expect roughly 8.7 wet days totalling 98.7mm. Comfortable conditions for being outdoors all day.
October in Washington averages a daily high of 20.8°C with nights around 11.3°C. Expect roughly 8.2 wet days totalling 93.2mm. Comfortable conditions for being outdoors all day.
November in Washington averages a daily high of 14.4°C with nights around 5.2°C. Expect roughly 8.1 wet days totalling 71.6mm. Generally workable, with some weather to plan around.
December in Washington averages a daily high of 9.3°C with nights around 1.3°C. Expect roughly 9.8 wet days totalling 86mm. 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. Washington peaks at 84.
Based on 30 years of records, April–May scores highest for comfort in Washington, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 31.7°C.
July is the wettest, averaging 117.5mm of rain across roughly 10.5 wet days.
January is the coolest month, with average daily highs around 7.1°C.