Last updated: February 24, 2025
December in National Harbor, United States offers a chilly yet captivating experience, with temperatures ranging from a brisk -10°C (14°F) at night to a mild 20°C (69°F) during the day. The average temperature settles around 5°C (42°F), providing a distinctly winter atmosphere. Visitors can expect approximately 89 mm (3.5 in) of precipitation across 9 days, contributing to the lush landscape and the holiday charm of the area. With an average humidity of 84%, the air carries a refreshing coolness, perfect for cozy festivities and exploring the scenic waterfront.
As December settles in at National Harbor, temperatures begin to reflect the chill of winter, with a marked drop from the milder autumn months. The month opens with minimum temperatures around -10°C (14°F), and while the average hovers at 5°C (42°F), daytime highs can still reach a comfortable 20°C (69°F). This transitional period showcases a blend of icy nights and relatively warm afternoons, encouraging locals and visitors alike to embrace the festive season amidst the brisk air. As the year winds down, the landscape transforms into a picturesque winter scene, nicely contrasting the summer's scorching highs of 38°C (102°F), reminding us that each season brings its own unique charm.
In December, National Harbor experiences a moderate precipitation level averaging 89 mm (3.5 in), marking a slight decrease from the more substantial rainfall of earlier months like August and July. With 9 days of precipitation this month, December continues to show a pattern of consistent moisture that has characterized the fall season. This trend aligns with the typical annual cycle, where rainfall peaks in the warmer months and tapers off towards winter. Despite the reduction in both the amount and frequency of precipitation compared to the peak summer months, December's rainfall contributes to the region's vibrant winter landscape, keeping the environment refreshed and seasonal activities thriving.
In December, National Harbor experiences a humidity level of 84%, slightly dipping from the peak of 85% observed in November. This trend marks a continuation of the area's generally high humidity levels throughout the winter months. The data shows that January usually starts off the year with a similar high humidity of 84%, suggesting a consistent winter pattern. As the seasons transition, humidity tends to decrease from May to August, reaching a low of 72% in August before climbing again in the fall. Overall, December's humidity, while on the higher side, fits seamlessly into the broader climate narrative of National Harbor, where moisture levels remain significant amid cooler temperatures.
As winter embraces National Harbor, December brings a modest UV Index of 3, indicating a moderate level of sun exposure. This trend marks a notable decline from the peak UV Index of 10 seen in the summer months, reflecting the seasonal shift that requires less vigilance against sunburn. With a recommended burn time of 30 minutes, residents and visitors alike can enjoy the outdoors with limited risk, reminiscent of January's similar index. Overall, the transition from the vibrant summer sun to the gentler winter rays showcases a clear pattern of changing UV exposure, underscoring the importance of adjusting sun safety practices throughout the year. For more insights, visit National Harbor UV Index.
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In December, National Harbor enjoys a notable 190 hours of sunshine, contributing to a cozy atmosphere as the year winds down. While it's a dip from the sun-soaked heights of July with a striking 357 hours, it's a significant shift from the earlier winter months of January and February, which see only 153 and 180 hours respectively. This gradual increase in daylight leading up to December reflects a broader trend of diminishing sunlight during the colder months. As the calendar year closes, the holiday season becomes brighter, inviting residents and visitors alike to bask in those precious sunlit moments, which, although fewer, are cherished against the backdrop of festive celebrations.
In December, the likelihood of sunny weather in National Harbor, United States, dips to 39%, marking it as one of the cloudier months of the year. This reflects a trend seen throughout the winter months, as the sunshine chances generally decrease after the more favorable conditions of September, which boasts a 55% chance of sun. November gives a slight boost with 58%, before falling into the cooler December climate. Historically, December aligns more closely with the gloomy skies typical of January and February, both of which are known for their low sunshine percentages. Thus, if you're planning a trip, it’s wise to prepare for possible overcast days as the year winds down.
As the year comes to a close in December, National Harbor experiences a familiar rhythm in daylight duration, offering approximately 9 hours of sunlight. This marks a return to the shorter days that begin in November and reflect the gradual decline seen since the peak summer months of June, which bask in 14 hours of daylight. The shift from longer to shorter days illustrates the transition of seasons, with daylight starting at 10 hours in February and gradually increasing until it peaks in May. With each passing month, the dance of daylight casts its spell over the region, and as December arrives, it invites the cozy embrace of winter with its reduced, yet still cherished, hours of sunlight.
As December rolls into National Harbor, the average wind speed settles at a gentle 2.8 m/s (6 mph), echoing the mellow breezes that have characterized the latter part of the year. Notably, the wind patterns have shown a gradual decline from the early months; January through April witnessed consistent speeds around 3.2 m/s (7 mph), creating a lively atmosphere. However, by the height of summer, winds dwindled to a calm 1.9 m/s (4 mph) in August, marking a seasonal low. As autumn approached, a slight uptick occurred, reflecting a transition back toward the more moderate winds of winter. This consistent yet gentle wind, typical for December, adds to the serene charm of the harbor, making it an inviting destination for those seeking a peaceful respite by the water.
The weather in National Harbor changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of December's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in National Harbor and find detailed weather information for every month.
In December, temperatures typically range from a minimum of -10°C (14°F) to a maximum of 20°C (69°F), with an average of 5°C (42°F). The month experiences about 89 mm (3.5 in) of precipitation over approximately nine days, with consistent humidity levels at 84%. In contrast, January sees slightly lower temperatures, with a minimum of -14°C (7°F) and an average of 3°C (38°F), while the maximum can reach 22°C (71°F). Precipitation decreases to about 61 mm (2.4 in) over seven days, maintaining the same humidity level of 84%. For a more detailed view of January weather patterns, you can check National Harbor weather in January.
In December, temperatures range from a frigid minimum of -10°C (14°F) to a pleasant maximum of 20°C (69°F), with an average of around 5°C (42°F). The month experiences a total precipitation of 89 mm (3.5 in) over approximately 9 days, with humidity levels reaching 84%. In contrast, February sees even colder minimum temperatures dropping to -14°C (7°F), though it can warm up to a maximum of 27°C (81°F), maintaining an average of 5°C (42°F). Precipitation increases slightly to 96 mm (3.8 in), occurring over 11 days, while humidity remains relatively stable at 83%. For a closer look at the weather specifics during February, you can visit National Harbor weather in February.
In December, temperatures can dip as low as -10°C (14°F), while averaging around 5°C (42°F) and reaching a maximum of 20°C (69°F). The month typically experiences 89 mm (3.5 in) of precipitation over 9 days, coupled with a relatively high humidity level of 84%. In contrast, March presents a milder climate, with minimum temperatures around -6°C (22°F) and an average temperature of 8°C (47°F), peaking at 29°C (84°F). Precipitation is slightly lower at 82 mm (3.2 in), also over 9 days, and humidity remains just a notch lower at 83%. For more specific weather details, check out National Harbor weather in March.
When comparing December and April weather, there is a notable shift in temperatures and conditions. December sees a much cooler climate, with minimum temperatures dipping to -10°C (14°F) and an average temperature of 5°C (42°F), while April enjoys milder conditions, with minimums around -1°C (31°F) and an average of 14°C (58°F). The maximum temperature in December can reach 20°C (69°F), whereas April can soar up to 33°C (92°F). Precipitation is slightly higher in April, totaling 102 mm (4.0 in) over 11 days, compared to December's 89 mm (3.5 in) over 9 days. Humidity remains fairly consistent, with December at 84% and April at 81%. For a detailed look at April's climate, you can visit National Harbor weather in April.
December's weather is characterized by much colder temperatures, with a minimum of -10°C (14°F) and an average of 5°C (42°F), while May enjoys significantly warmer conditions, starting from a minimum of 3°C (37°F) and averaging 19°C (67°F). Precipitation levels are also higher in May, totaling 121 mm (4.8 in) over 12 days compared to December's 89 mm (3.5 in) over 9 days. Additionally, December has a higher humidity level at 84%, while May's humidity is slightly lower at 78%, contributing to a more comfortable feel during the warmer months. For a detailed look at the weather trends, you can check out National Harbor weather in May.
In December, the weather is significantly cooler, with temperatures ranging from a minimum of -10°C (14°F) to a maximum of 20°C (69°F) and an average of 5°C (42°F). Precipitation occurs on about 9 days, totaling 89 mm (3.5 in), and the humidity is relatively high at 84%. In contrast, June boasts much warmer temperatures, with a minimum of 9°C (49°F) and an impressive maximum of 37°C (98°F), averaging around 24°C (76°F). Rain is more frequent in June, with 13 days of precipitation adding up to 107 mm (4.2 in), and humidity is slightly lower at 79%. For a detailed look at what to expect weather-wise in June, check out National Harbor weather in June.
The weather conditions in December and July contrast significantly. In December, temperatures range from a chilly minimum of -10°C (14°F) to a milder maximum of 20°C (69°F), with an average of around 5°C (42°F). The month is characterized by high humidity at 84% and approximately 89 mm (3.5 in) of precipitation over 9 days. In contrast, July brings a much warmer climate, with minimum temperatures starting at 16°C (61°F) and reaching a scorching maximum of 38°C (102°F), averaging 27°C (81°F). This summer month is also wetter, with 132 mm (5.2 in) of precipitation occurring over about 12 days, while humidity is relatively lower at 74%. For those interested in a detailed overview of July weather patterns, check out National Harbor weather in July.
December and August present strikingly contrasting weather patterns. In December, temperatures can drop as low as -10°C (14°F) at night, while averaging around 5°C (42°F) during the day, with a maximum reaching 20°C (69°F). The month is characterized by high humidity at 84% and about 9 days of precipitation, totaling 89 mm (3.5 in). In stark contrast, August offers much warmer temperatures, with minimums around 15°C (59°F), an average of 25°C (78°F), and maximums soaring to 37°C (99°F). With 15 days of precipitation and a total of 146 mm (5.7 in), the humidity is lower at 72%. The differences between these months highlight the seasonal variations that can significantly affect daily life and activities. For more details, you can check out National Harbor weather in August.
December and September present notably contrasting weather patterns. December features a chilly climate with temperatures ranging from a minimum of -10°C (14°F) to an average of 5°C (42°F) and a maximum of 20°C (69°F). Despite a slightly lower precipitation level of 89 mm (3.5 in) over 9 days, the humidity is relatively high at 84%, contributing to a cold, damp environment. In contrast, September offers much warmer conditions, with temperatures starting at a minimum of 6°C (44°F) and soaring to an average of 22°C (73°F), peaking at a sizzling 37°C (99°F). Precipitation in September is marginally higher at 93 mm (3.7 in) across 11 days, coupled with lower humidity at 75%. To explore more about the weather specifics in September, visit National Harbor weather in September.
In comparing the weather between October and December, one can observe significant differences in temperature and conditions. October experiences a much milder climate, with average temperatures ranging from a chilly 2°C (36°F) at night to a warm 36°C (97°F) during the day, while December's daytime highs peak at a much cooler 20°C (69°F). Precipitation levels are fairly close, with October receiving 105 mm (4.2 in) and December slightly less at 89 mm (3.5 in), though both months see rain for about 9 days. Additionally, December tends to be more humid, with an average of 84%, compared to October's 81%. For specific weather insights, you can check the National Harbor weather in October.
When comparing the weather between November and December, notable differences emerge. December generally experiences colder conditions, with minimum temperatures dropping to -10°C (14°F) compared to November's milder minimum of -5°C (23°F). While the average temperature in December is around 5°C (42°F), November boasts a higher average of 9°C (48°F). Maximum temperatures also reflect this chill, with December peaking at 20°C (69°F) versus November's maximum of 26°C (78°F). Precipitation is slightly higher in December at 89 mm (3.5 in) compared to 77 mm (3.0 in) in November, with December also having more rainy days (9 days) than November (7 days). Humidity levels are relatively similar, with December at 84% and November at 85%. For those interested in more detailed insights, you can explore the specific conditions in National Harbor weather in November.
As December graces National Harbor, the weather shifts considerably from the milder months, bringing a crisp chill that sets the tone for winter. With average temperatures dipping to 5°C and the potential for lows reaching -10°C, residents and visitors alike should bundle up against the cool air. Precipitation becomes more frequent, with nearly nine days of rain, resulting in a total of 89 mm throughout the month. Despite the drop in temperature, the heightened humidity at 84% can make the air feel more biting. Ultimately, December's weather serves as a reminder of the stark seasonal transition, contrasting beautifully with the warmer months. For more insights into the climate of this vibrant area, check out National Harbor Climate.