Monthly weather averages & travel planning

North America › 🇺🇸 United States › Washington DC
Updated: March 2026
July is a fair time to visit Washington DC (5/10). With 12 daily sunshine hours and only 13 rain days, this month delivers genuinely reliable outdoor conditions, ranking it the sunniest month of the year in Washington DC. Culture-focused travellers and those who prefer lighter crowds will find July a practical choice, with prices running lower than peak July without sacrificing all the good weather. August offers a similar profile at lower hotel rates if dates are flexible. The main practical note: Washington DC's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: accommodation is generally available without long lead times, and flight prices are typically lower than peak season. Flexible travellers will find the best deals by booking 2-4 weeks ahead. Mid-week arrivals consistently unlock lower hotel rates than weekend check-ins.
Washington DC in July rewards travelers with average highs of 31°C and overnight lows around 21°C. Expect around 13 rainy days, so a compact umbrella is worth carrying. With 12 daily sunshine hours on average, conditions are warm and inviting for outdoor exploration.
31°C
88°F
Avg High
21°C
70°F
Avg Low
13 days
110 mm total
Rain Days
12h
per day avg
Sunshine
65%
Moderate
Humidity
The 10°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. Humidity averages 65%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. UV index averages 9 this month, classed as high to very high. SPF 30+ sunscreen, a brim hat, and sunglasses are not optional between 10am and 4pm. Winds are calm at an average 13 km/h, so wind-chill is not a factor in planning your clothing. In Fahrenheit: 88°F average high, 70°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Packing for Washington DC in July means dressing for 31°C days and 21°C evenings. A lightweight linen or cotton shirt with loose-fit trousers or a sundress handles the 31°C daytime heat. Evening temperatures settle at 21°C, a modest 10°C drop that a light cardigan or denim jacket covers. For footwear, breathable walking sandals work for casual exploration, but closed-toe trainers are better for uneven surfaces in the historic centre. With 13 rain days expected, a compact travel umbrella is worth the bag space. A waterproof jacket is better than an umbrella if you plan full-day outdoor routes.
Local tip: Layers are more practical than a single heavy garment in Washington DC. The day-to-evening temperature shift rewards packing a versatile mid-layer you can add or remove as conditions change.
July has no major festivals or public holidays in Washington DC, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.
Based on 31°C average highs and 13 rainy days
July in Washington DC reflects a mid-latitude climate pattern, with temperatures averaging 31°C by day and 21°C overnight. The city sits at 39 degrees north latitude, where the balance between solar radiation and heat loss drives conditions that are neither extreme nor static. The warm temperatures reflect a stable high-pressure pattern typical of the season, which suppresses cloud formation and concentrates solar energy at the surface. Day-to-night temperature variation of 10°C is moderate and manageable with a single mid-layer. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Washington DC in July
July ranks 1st sunniest of the year in Washington DC, with an average 12 daily sunshine hours. The driest months are October, November, and January. July is the hottest month (31°C avg high); January is the coolest (6°C). From here, temperatures fall 1°C into August. Compared to last month (June: 29°C high, 12 rain days), July is warmer and wetter. July is among the top three sunniest months to visit Washington DC.
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 6°C | -2°C | 9 | 7h | View |
| February | 8°C | -1°C | 9 | 8h | View |
| March | 13°C | 2°C | 10 | 8h | View |
| April | 19°C | 8°C | 10 | 9h | View |
| May | 24°C | 13°C | 12 | 10h | View |
| June | 29°C | 18°C | 12 | 11h | View |
| July | 31°C | 21°C | 13 | 12h | View |
| August | 30°C | 20°C | 11 | 11h | View |
| September | 26°C | 17°C | 10 | 9h | View |
| October | 20°C | 11°C | 8 | 8h | View |
| November | 13°C | 5°C | 8 | 7h | View |
| December | 8°C | 0°C | 9 | 6h | View |
January
9 rain days, 7h sun
February
9 rain days, 8h sun
March
10 rain days, 8h sun
April
10 rain days, 9h sun
May
12 rain days, 10h sun
June
12 rain days, 11h sun
July
13 rain days, 12h sun
August
11 rain days, 11h sun
September
10 rain days, 9h sun
October
8 rain days, 8h sun
November
8 rain days, 7h sun
December
9 rain days, 6h sun
Data Sources for Washington DC
Climate normals represent 30-year averages (1991-2020). Individual years may vary.