Weather in Washington in July
United States · 20-year averages, July
Shoulder season. July is shoulder season in Washington — cheaper, quieter, and a genuine gamble. Highs average 31.1 °C, lows 21.1 °C, and rain falls on 14 days — nothing in the month is working against you.
July ranks 9 of 12 in Washington: past the worst of the year but short of October, which is the month to book if the dates are open.
Rain on 14 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 31.1 °C days and 21.1 °C nights; the spread matters more here than any single number.
What the averages hide
Averages flatten a month, and this one hides a few things: 20 days top 30 °C, making the heat continuous rather than occasional. Across the twenty years measured, the hottest July day reached 40.7 °C and the coldest night fell to 13 °C, and the wettest single day dropped 101 mm — roughly 87% of the month's rain in one day.
July is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest July on record still delivered 248 mm against 58 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 116 mm average is a reasonable planning figure, not a promise.
Wind is light at 7.2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 69%.
How July sits in the year
Temperatures hold steady either side: 28.1 °C in June, 31.1 here, 30.6 in August. Nothing about the timing within the month matters much.
Daylight in July
July is at or near the longest days of Washington's year: 14.7 hours of daylight, losing 0.6 hours across the month. Evenings are the real gain — dinner outdoors still happens in full light.
An inland climate
With no coast nearby, the year swings a fair way — 34.4 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.
How busy it gets
Busy. Popular without being frantic; book the things you care about, improvise the rest.
Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.
July in Washington versus nearby
If Washington is one option among several, the nearby comparison is worth making. Richmond is a better bet in July — 9.7 °C cooler, 9 days less rain. Philadelphia is close enough to be a coin toss — within a degree on temperature, the same number of rain days.
So: July is a compromise. October is 26 points better and is what Washington is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.
Every month in Washington
| Month | High °C | Low °C | Rain days | Rain mm | Humidity % | Daylight h | Score |
|---|---|---|---|---|---|---|---|
| January | 4.8 | -3.3 | 8 | 67 | 82 | 9.7 | 30 |
| February | 6.5 | -2.6 | 9 | 70 | 80 | 10.7 | 36 |
| March | 11.6 | 1.2 | 9 | 84 | 79 | 11.9 | 55 |
| April | 18.1 | 7 | 10 | 92 | 76 | 13.2 | 74 |
| May | 23.1 | 12.8 | 13 | 110 | 78 | 14.3 | 75 |
| June | 28.1 | 18.1 | 14 | 118 | 74 | 14.9 | 67 |
| July | 31.1 | 21.1 | 14 | 116 | 69 | 14.7 | 55 |
| August | 30.6 | 20.6 | 13 | 110 | 70 | 13.7 | 59 |
| September | 27.1 | 16.7 | 10 | 107 | 72 | 12.5 | 79 |
| October | 20.2 | 10 | 9 | 105 | 76 | 11.3 | 81 |
| November | 13.5 | 3.8 | 8 | 80 | 79 | 10.1 | 62 |
| December | 7.5 | -0.5 | 9 | 95 | 83 | 9.5 | 39 |
See all twelve months in Washington, or where else to go in July.
Planning the rest of the trip
- Flight time to Washington how long you are actually in the air
- Washington time zone and the difference from home
- Days until your trip count down to the departure date
- Gyms & clubs in Washington keep training while you are there