National Harbor (MD) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit National Harbor.
Climate overview of National Harbor
Temperatures in National Harbor, Maryland, United States of America, vary greatly throughout the year. July is the hottest month at 32°C (90°F), while January is the coldest at 7°C (45°F).
The city receives considerable rain/snowfall, with around 1151 mm (45 in) annually. June is the wettest month. The sunniest month is June, with 9.4 hours of sunshine per day on average.
National Harbor Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in National Harbor — and find the best time to visit.
Monthly Temperature in National Harbor
The climate in National Harbor is known for significant temperature differences throughout the year, making the weather dynamic. Typically, average maximum daytime temperatures range from a very warm 32°C (90°F) in July to a chilly 7°C (45°F) in the coolest month, January.
Nights vary from 21°C (70°F) in July to around -2°C (28°F) during the colder months.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in National Harbor
National Harbor has a notably wet climate with abundant precipitation, recording 1151 mm (45 in) of rain/snowfall per year. The climate in National Harbor shows significant variation throughout the year. Expect high rainfall in June, the wettest month, with an average of 149 mm (5.9 in) of precipitation over 13 rainy days.
In contrast, the driest month February offers drier and sunnier days, with around 67 mm (2.6 in) of rainfall over 10 rainy days. For more details, please visit our National Harbor Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in National Harbor
For those who appreciate different seasons, National Harbor serves as an ideal destination. Expect longer, more sun-filled days in June with an average of 9.4 hours of sunshine daily, and embrace the darker days in December, offering only 4.3 hours of daily sunlight.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in National Harbor by Month
The relative humidity is high throughout the year in National Harbor.
The city experiences its highest humidity in August, reaching 69%. In March, the humidity drops to its lowest level at 58%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Wind Speed in National Harbor
The mean wind speed varies between 4 m/s (8 knots) and 5 m/s (10 knots) throughout the year. It is lowest in May, June, July, August, September, October, November and December and highest during January, February, March and April. What does this mean?
The mean monthly wind speed over the year (meters per second)
Best Time to Visit National Harbor
Frequently asked questions about the climate in National Harbor
What is the best time to visit National Harbor?
April typically offers the most optimal weather in National Harbor. In contrast, January, February and December tend to have less optimal conditions.
What temperatures can I expect in National Harbor?
Daytime highs range from 7°C (45°F) in January to 32°C (90°F) in July. Nighttime lows range from -2°C (28°F) to 21°C (70°F). Temperatures vary considerably through the year.
How much rain does National Harbor get?
Annual rainfall is around 1151 mm (45 in). June is the wettest month with 149 mm (5.9 in), while February is the driest with 67 mm (2.6 in).
How sunny is National Harbor?
National Harbor receives around 2,520 hours of sunshine per year. June is the sunniest month with 282 hours, while December is the cloudiest with just 130 hours. Overall, National Harbor enjoys abundant sunshine.
National Harbor 3-Day Forecast
National Harbor (MD) 3-Day Forecast
National Harbor on the map
National Harbor is highlighted — select any city to see its climate.
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