National Harbor Weather in August

National Harbor in August sees very high temperatures, with highs around 31°C (88°F) and overnight lows of 20°C (68°F). Rainfall is fairly high at around 94 mm (3.7 in) on average, so pack waterproofs just in case.

Rainfall in National Harbor in August

Typically, about 10 days will experience rainfall, with an average of 94 mm (3.7 in) for the month. Rainfall intensity is on the higher side this month. Expect more substantial showers rather than light, passing rain.

Temperature in National Harbor in August

Daytime temperatures in National Harbor reach 31°C (88°F) in August, dropping to 20°C (68°F) at night. It's usually most comfortable outside during the morning and later in the day. Nights remain mild at 20°C (68°F), making evenings a pleasant time to be outdoors.

Sunshine in National Harbor in August

There are approximately 262 hours of sunshine this month, resulting in mostly clear days.

Wind Speed in National Harbor in August

August sees wind speeds averaging 4 m/s (8 knots). You'll experience variable conditions with moderate winds that create small waves on water and keep branches moving. Conditions range from light winds to moderate breezes throughout the month.

For National Harbor itself, April generally stands out with the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.

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For a detailed overview over the year and the best time to visit the United States of America, check out our National Harbor's climate page.

National Harbor Temperature in August

Min Temperature 20°C (68°F)  

Max Temperature 31°C (88°F)  

Chance of Rain 34%  

Precipitation 94 mm (3.7 in)  

Rainy days 10 days  

Humidity 69% *  

Windspeed 4 m/s (8 knots) *  

Sunshine 262 hours *  

Percentage Sunshine 62% *  

* Data from: Washington DC, the United States of America (7 KM, 4 Miles).

What to Wear in National Harbor in August

Warm weather calls for comfortable, breathable clothing in August. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). High rain levels are expected, so pack waterproof gear and an umbrella or poncho. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.

What To Do in National Harbor in August

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

9/10

Cycling

7/10

Walking

7/10

Camping

8/10

Outdoor sports

7/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United States of America, check out our National Harbor's climate page.

More climate data for National Harbor

Temperature Rainfall Sunshine Humidity Wind Speed

See the full National Harbor climate overview or explore weather in the United States of America.