Last updated: February 24, 2025
In December, Philadelphia experiences a varied climate, with temperatures ranging from a brisk maximum of 16°C (61°F) to a chilling minimum of -27°C (-17°F). The average temperature lingers around a frosty -2°C (28°F), making this month one of the coldest in the city. Accompanying the chill, precipitation is notable, with an average of 98 mm (3.8 in) spread over 13 days, resulting in a damp atmosphere characterized by an humidity level of 89%. This blend of cold temperatures and frequent rain underscores the need for preparation when navigating the wintery streets of Philadelphia.
In December, Philadelphia experiences a striking transition into winter, marked by significantly cooler temperatures. The month sees daily lows averaging around -2°C (28°F), with occasional dips to a bracing -27°C (-17°F), hinting at the chill that accompanies the season. Daytime highs tend to be milder, reaching up to 16°C (61°F), but overall, there's a distinct drop from the milder autumn temperatures of November. This cooling trend sets the stage for the deep winter months ahead, creating a crisp, festive atmosphere throughout the city as residents and visitors alike bundle up to enjoy seasonal activities against the backdrop of chilly but manageable weather.
In December, Philadelphia experiences an average precipitation of 98 mm (3.8 in) across 13 days, marking a notable continuation of the wet fall season. This month typically sees a slight decrease from the wetter autumn months, particularly October, which recorded a hefty 160 mm (6.3 in). As winter approaches, December's precipitation levels are still significant, falling just below the city’s yearly peak in April at 130 mm (5.1 in). The consistent pattern of precipitation days throughout the year, with December closely aligning with the averages observed in earlier months, highlights a climate that remains dynamic yet predictable, as residents brace themselves for the upcoming chill of winter.
In Philadelphia, December marks a noteworthy shift in humidity levels as they settle at 89%, slightly higher than the previous month. The trend over the year reveals a captivating rhythm; while January and February hold steadfast with a high 93%, humidity begins to decrease gradually through the spring and summer months, hitting a low of 67% in August. As fall approaches, humidity rises again, illustrating a consistent pattern of increased moisture in the air during the colder months. By December, residents experience a noticeable return to the heavier, more humid conditions reminiscent of winter, standing just below November's 88%. This cyclical ebb and flow not only defines Philadelphia's climate but also shapes the local experience as the city transitions into the heart of winter.
In December, Philadelphia experiences a low UV Index of 2, reflecting the city’s cozy winter embrace. With a burn time of 45 minutes, outdoor enthusiasts can enjoy leisurely strolls without the worry of sunburn. This trend of decreasing UV levels highlights a seasonal dip from the very high indices of summer months, where UVI reached up to 9, indicating a stark contrast in sun exposure throughout the year. As December brings shorter days and lower sun angles, residents can take advantage of the milder UV conditions while still being mindful of their skin health. For more detailed insights, check out the Philadelphia UV Index.
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December in Philadelphia brings a crisp chill and 117 hours of sunlight, marking a transition as the city shifts into winter's embrace. This month sees a noticeable dip compared to the vibrant 339 hours of sunshine in July, yet it holds its own charm. As the year progresses from the sun-drenched days of summer, the gradual decrease in sunlight hours illustrates a clear seasonal trend. December's hours are a reminder of the rich contrast found throughout the year, starting from a luminous 273 hours in May to the 145 hours of February. While the shorter days may signal the cozy onset of winter, they also invite a sense of serenity as the city shines quietly under the festive lights.
December in Philadelphia typically brings a chill in the air and a lower chance of sunshine, with only a 23% likelihood of sunny days. This marks the tail end of the year when the probability of basking in bright sunlight dips significantly, especially when compared to the blossoming months of March and May, which see chances as high as 46% and 43%, respectively. Even as the autumn months display a pleasing 41% chance in November, December's overcast skies often herald the arrival of winter. These trends suggest that while the holiday season may be beautiful, it is also characterized by a more subdued sun, inviting residents to cozy indoors as they embrace the festive cheer.
In Philadelphia, December brings the shortest daylight of the year, with only 8 hours to illuminate the city. As the calendar moves from the vibrant glow of summer, where both June and July bask in a generous 15 hours of sunlight, the trend clearly reveals a gradual descent into the darker months. Following the warm embrace of spring and summer, October and November lay the groundwork for winter’s arrival, each slipping back to 10 and 9 hours of daylight, respectively. As December settles in, the stark contrast from the peak summer days reinforces the cyclical nature of light throughout the year, reminding us that with every winter's night, brighter days are just around the corner.
As December rolls into Philadelphia, the wind begins to pick up, with an average speed of 3.7 m/s (8 mph), slightly breezier than in the chillier months of January and July, which each average 2.6 m/s (6 mph). This increment reveals a subtle trend as the year progresses, where the winds often strengthen in late fall before settling back down for winter. From a calm start of 2.6 m/s in January, the winds gradually escalate, peaking in December, showcasing a lively transition into the end of the year. With gusts becoming more pronounced, December's breeze adds a crisp energy to the city, hinting at the vibrant changes in store as we welcome the new year.
The weather in Philadelphia 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 Philadelphia and find detailed weather information for every month.
December and January showcase notable differences in weather, with January generally being colder than December. December experiences minimum temperatures around -27°C (-17°F) and averages at -2°C (28°F), while January sees even more frigid minimums reaching -33°C (-27°F) and an average of -6°C (22°F). Both months have similar maximum temperatures, with December peaking at 16°C (61°F) and January slightly lower at 14°C (58°F). In terms of precipitation, December has slightly more at 98 mm (3.8 in), occurring over 13 days, compared to January's 86 mm (3.4 in) over 12 days. The humidity levels are also higher in January, at 93%, compared to December's 89%. For a detailed look at the weather trends, you can visit Philadelphia weather in January.
December and February present strikingly similar winter climates, with both months featuring minimum temperatures plummeting to around -27°C (-17°F). However, December tends to be slightly milder on average, with an average temperature of -2°C (28°F) compared to February's -4°C (25°F). Despite the overall chill, December has a maximum temperature reaching 16°C (61°F), while February's peaks are slightly lower at 15°C (60°F).
Precipitation is another aspect where the months differ; December sees 98 mm (3.8 in) of precipitation over 13 days, whereas February has less, at 84 mm (3.3 in) over 12 days. Humidity levels are higher in February at 93%, compared to December’s 89%.
For detailed weather updates, you can check Philadelphia weather in February.
When comparing December and March weather, we see notable differences in temperature and precipitation patterns. In December, the minimum temperature can drop to -27°C (-17°F), with an average of -2°C (28°F) and a maximum of 16°C (61°F). The month experiences around 98 mm (3.8 inches) of precipitation over 13 days, accompanied by high humidity levels of 89%. In contrast, March presents milder conditions, with minimum temperatures at -22°C (-7°F), an average of 0°C (32°F), and a maximum reaching up to 21°C (70°F). Precipitation in March is slightly lower at 88 mm (3.5 inches) over 12 days, and humidity is marginally lower at 86%. For those interested in specific weather statistics, you can explore Philadelphia weather in March.
When comparing the weather in December and April, notable differences emerge. December is characterized by colder temperatures, with a minimum of -27°C (-17°F) and an average around -2°C (28°F), while April sees a milder minimum of -7°C (19°F) and an average of 7°C (44°F). The maximum temperatures in December peak at 16°C (61°F), but April can soar up to 30°C (86°F), indicating a significant warming trend as spring approaches. Precipitation is relatively high in both months, with December receiving 98 mm (3.8 in) over 13 days, compared to April's 130 mm (5.1 in) over 14 days. Despite the increased rainfall in April, humidity levels drop slightly from December's 89% to 82%. This transition from the chill of winter to the budding warmth of spring is further explored at Philadelphia weather in April.
December and May exhibit stark contrasts in weather patterns. In December, temperatures plunge to a minimum of -27°C (-17°F) and average around -2°C (28°F), with a maximum of only 16°C (61°F). The month witnesses about 98 mm (3.8 in) of precipitation over 13 days, accompanied by a high humidity level of 89%. In sharp contrast, May experiences a milder climate, with temperatures ranging from a minimum of -2°C (29°F) to an average of 14°C (57°F) and peaking at 32°C (90°F). Precipitation slightly increases to 104 mm (4.1 in) over the same number of days, but humidity is lower at 75%. For more details about May weather conditions, visit Philadelphia weather in May.
December and June present stark contrasts in weather. In December, temperatures can plummet as low as -27°C (-17°F) and typically average around -2°C (28°F), while June enjoys much milder conditions with a minimum temperature of 3°C (38°F) and an average of 19°C (66°F). Total precipitation for both months is similar, with December receiving 98 mm (3.8 in) and June slightly more at 104 mm (4.1 in), and both months experiencing precipitation on about 13 days. However, humidity is significantly higher in December at 89%, compared to June’s more comfortable 68%. These differences highlight the seasonal transitions, making June a much warmer and drier month compared to the frigid and damp December. For more information, check Philadelphia weather in June.
December and July present starkly contrasting weather conditions. December experiences frigid temperatures, with a minimum of -27°C (-17°F) and an average of -2°C (28°F), while July boasts much warmer ranges, starting from a minimum of 9°C (49°F) and averaging 22°C (72°F), reaching maximums of 35°C (95°F). Precipitation is also notable in both months, with December receiving 98 mm (3.8 in) over 13 days and July seeing a slightly higher total of 137 mm (5.4 in) across 14 days. Additionally, December's high humidity at 89% contributes to a chilly atmosphere, whereas July's humidity of 69% lends a warmer, more comfortable feeling. For more detailed insights on summer weather, check out Philadelphia weather in July.
December and August present starkly contrasting weather conditions. In December, temperatures can plunge as low as -27°C (-17°F), with an average temperature of -2°C (28°F) and a maximum of 16°C (61°F). This winter month also experiences high humidity at around 89% and significant precipitation over 13 days, totaling 98 mm (3.8 in). Conversely, August boasts a much milder climate with minimum temperatures around 7°C (44°F) and average highs reaching 31°C (89°F). This summer month sees an average temperature of 21°C (70°F) and lower humidity levels at 67%, with slightly increased precipitation of 106 mm (4.2 in) spread over 14 days. For more details on August weather in Philadelphia, you can visit Philadelphia weather in August.
December and September present stark contrasts in weather conditions. December features a chilly climate with temperatures ranging from a frigid minimum of -27°C (-17°F) to a mild maximum of 16°C (61°F), averaging around -2°C (28°F). It also sees higher precipitation levels, totaling 98 mm (3.8 in) over 13 days, with a humidity level of 89%. In contrast, September offers a much warmer experience, with temperatures fluctuating from a minimum of 0°C (33°F) to a maximum of 32°C (89°F), averaging 17°C (62°F). This month experiences less precipitation at 75 mm (3.0 in) across 9 days and boasts a lower humidity level of 72%. For more information specific to September weather in Philadelphia, you can check this link: Philadelphia weather in September.
In comparing December and October, the weather exhibits notable contrasts. December experiences much colder temperatures, with a minimum of -27°C (-17°F) and an average of -2°C (28°F), while October is significantly milder, boasting a minimum of -3°C (26°F) and an average of 11°C (52°F). Additionally, December has a maximum temperature of 16°C (61°F), compared to October's peak of 26°C (80°F), showcasing a shift to chillier conditions as the year comes to a close. Precipitation also varies, with December receiving 98 mm (3.8 in) over 13 days and October seeing higher totals of 160 mm (6.3 in) across 14 days. Humidity levels are relatively high in both months, though December is slightly more humid at 89%, compared to October's 83%. For more detailed insights, you can refer to Philadelphia weather in October.
In comparing the weather of December to November, December tends to be colder on average, with temperatures ranging from a minimum of -27°C (-17°F) to a maximum of 16°C (61°F), while November experiences milder temperatures with a minimum of -15°C (6°F) and a maximum of 22°C (73°F). Additionally, December sees slightly less precipitation at 98 mm (3.8 in) over 13 days, compared to November's 119 mm (4.7 in) over 14 days. Humidity remains relatively consistent, with December having a humidity level of 89% versus November's 88%. Overall, December features a sharper drop in temperatures, marking a significant transition into winter. For more detailed weather insights, check Philadelphia weather in November.
As December settles over Philadelphia, the weather takes a dramatic turn, showcasing cooler temperatures and increased precipitation compared to the milder months preceding it. The chill in the air, with temperatures averaging around freezing, creates a crisp atmosphere that contrasts sharply with the autumn's gentler embrace. Additionally, December is marked by higher humidity levels, making the cold feel more penetrating. With nearly half the month experiencing precipitation, it's a stark reminder that winter is just around the corner. For more insights into the annual shifts in weather, visit Philadelphia Climate.