Last updated: February 24, 2025
January in Philadelphia brings a mix of chill and occasional warmth, with maximum temperatures reaching up to 20°C (68°F), while the average hovers around 2°C (36°F). The month can be quite brisk, as minimum temperatures can plummet to a frigid -17°C (1°F). While residents brace for the cold, they can also expect about 63 mm (2.5 in) of precipitation over 9 days, contributing to an average humidity of 84% that enhances the winter atmosphere. This blend of conditions creates a unique winter experience, making January a time of both beauty and challenge in the City of Brotherly Love.
In January, Philadelphia experiences a stark mix of temperatures, characterized by frigid lows that reach as low as -17°C (1°F) and a moderate average of 2°C (36°F). While the city endures cold snaps, it can also bask in surprising highs, with maximum temperatures occasionally soaring up to 20°C (68°F). This fluctuation highlights a transitional phase in winter, as the city emerges from the deep freeze of December and hints at the mildness of February, where temperatures continue to creep upwards. Overall, January's weather embodies the unpredictable nature of winter in Philadelphia, offering both chilly days and unexpected warmth, setting the stage for the gradual rise into the more temperate spring months ahead.
In January, Philadelphia experiences a relatively mild start to the year with 63 mm (2.5 in) of precipitation spread over 9 days. This sets the stage for a gradual increase in rainfall as winter transitions into spring, with February seeing a significant jump to 108 mm (4.3 in) across 11 days. As the months progress, the city consistently receives higher precipitation, peaking in May with 133 mm (5.2 in) over 14 days. Interestingly, both July and August maintain this trend, reflecting summer’s peak in moisture with 131 mm and 134 mm, respectively. As autumn approaches, the precipitation begins to taper off, illustrating a clear seasonal rhythm where January’s relatively low totals contrast sharply with the wetter months that follow, indicating that Philadelphia’s weather is as dynamic as its vibrant city life.
In January, Philadelphia experiences a high relative humidity of 84%, establishing a notably damp atmosphere to kick off the year. This trend of elevated moisture continues into February and March, where humidity remains consistently at 83%. As spring approaches, humidity levels gradually decline, reaching 81% by April and further dipping to 78% in May. The summer months bring a brief respite with lower levels, peaking in July at 74%, but as fall settles in, humidity begins to rise again, marking November as the most humid month with 85%. This cyclical pattern showcases Philadelphia's seasonal humidity variations, where the chilly winter transitions into a more temperate spring and a drier summer, before returning to the dampness of winter once again.
In January, Philadelphia experiences a moderate UV Index of 3, allowing for about 30 minutes of exposure before the risk of burning increases. As the months progress, the UV Index trends upward, peaking at 10 in both May and June, where sun protection becomes crucial with just 15 minutes of burn time. The transition from winter to spring brings noticeable changes in UV exposure, particularly in March when the Index rises to 6, indicating a shift towards higher risks. By April, it climbs to 9, further emphasizing the need for vigilance as sunny days return. Interestingly, the UV levels remain quite high throughout the summer months, only beginning to taper off in September. As the year closes, both November and December see a return to a moderate level, with indices of 4 and 3 respectively, echoing the trends observed in January. To explore the comprehensive UV patterns for the year, check out Philadelphia UV Index.
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In January, Philadelphia basks in approximately 144 hours of sunshine, setting a modest tone for the year ahead. As winter gives way to spring, the city sees a steady increase in sunlight, with February enjoying 174 hours, and March making a notable leap to 245 hours. The trend continues into April with 246 hours, leading to a vibrant May that embraces a welcoming 273 hours of sun. This upward trajectory peaks in the summer, reaching a sun-soaked 346 hours in July, before gradually tapering off in August with 309 hours. As the days begin to shorten, September and October present 264 and 223 hours respectively, while November and December close the year with 221 and 179 hours. Overall, Philadelphia’s sunshine patterns reveal a captivating ebb and flow that reflects the changing seasons, offering both bright summer days and the cozy charm of winter light.
In Philadelphia, January brings a 45% chance of sunny weather, placing it in a favorable position compared to the subsequent month of February, which plummets to only 28%. As winter transitions into spring, the likelihood of sunshine gradually increases, peaking in March at 55%. Interestingly, April, a month often associated with blossoming flowers and vibrant days, shows a slightly lower chance of sunshine at 44%. This fluctuation suggests that while January offers a reasonable expectation of sunny days, it's the arrival of March that truly marks the turning point towards brighter skies, with notable sunny prospects returning in early fall, as seen in September's 52% chance. Overall, January may not be the sunniest month, but it hints at the brighter days that lie just ahead.
In Philadelphia, January heralds the year's shortest daylight duration, with only 9 hours of light gracing the city. As the month progresses into February, daylight begins to stretch its limbs, extending to 10 hours. By March, the trend continues upward, providing 11 hours of sunshine, a promising signal of spring’s arrival. This steady increase peaks in May and June, where residents enjoy a vibrant 14 hours of daylight, perfect for outdoor activities and social gatherings. As summer fades into autumn, daylight gradually diminishes, tapering down to 12 hours in September and reverting to 9 hours by November and December. This rhythmic ebb and flow of daylight not only marks the seasons but also influences the lifestyle and activities of Philadelphia’s residents throughout the year.
In Philadelphia, January brings a gentle breeze with an average wind speed of 3.3 m/s (7 mph), marking the beginning of a subtle upward trend as the city transitions into the new year. As we move into February, the winds pick up slightly to 3.5 m/s (8 mph), foreshadowing the invigorating gusts that accompany the arrival of spring. Interestingly, the wind speed reaches its peak in March at 3.7 m/s (8 mph), before settling back to 3.5 m/s in April, creating a rhythmic ebb and flow as warmer months approach. By May, the winds begin to calm, dropping to 3.1 m/s (7 mph) and continuing their decline through the summer months, ultimately reaching their lowest point in August at 2.2 m/s (5 mph). This consistent decrease highlights Philadelphia's shift to warmer, sunnier days, only to regain a bit of momentum as autumn sets in. Overall, January's winds serve as a tranquil harbinger of the changing seasons, paving the way for both brisk clarity and the gentle warmth ahead.
The weather in Philadelphia changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of January'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.
January's weather is characterized by colder temperatures, with a minimum of -17°C (1°F) and an average of 2°C (36°F), while February sees slightly milder conditions, starting with a minimum of -15°C (5°F) and an average of 4°C (39°F). One notable difference is in precipitation; January receives 63 mm (2.5 in) over 9 days, whereas February experiences more rain, totaling 108 mm (4.3 in) across 11 days. Humidity levels remain similar, with January at 84% and February slightly lower at 83%. For more detailed information, you can check Philadelphia weather in February.
In January, Philadelphia experiences colder temperatures, with a minimum of -17°C (1°F) and an average of around 2°C (36°F), while March sees a noticeable warming trend, where the minimum is -11°C (12°F) and the average rises to 7°C (44°F). The maximum temperatures in March can reach up to 28°C (83°F), significantly higher than the January maximum of 20°C (68°F). Although January has slightly less precipitation at 63 mm (2.5 in) over 9 days, March encounters more rainfall, totaling 107 mm (4.2 in) over 10 days. Despite this increase in precipitation, humidity levels are comparable, with January at 84% and March at 83%. For a deeper dive into what to expect, visit Philadelphia weather in March.
In January, temperatures in the region can dip as low as -17°C (1°F), with an average temperature around 2°C (36°F) and highs reaching up to 20°C (68°F). This month experiences around 63 mm (2.5 in) of precipitation over approximately 9 days, coupled with a relatively high humidity level of 84%. In contrast, April sees a considerable rise in temperatures, with minimums around -2°C (29°F), averages climbing to 12°C (55°F), and maximums soaring up to 32°C (89°F). Rainfall increases as well, totaling 105 mm (4.1 in) across about 11 days, while humidity remains slightly lower at 81%. For more details on temperature and precipitation trends, visit Philadelphia weather in April.
January and May exhibit stark contrasts in weather patterns. In January, the temperatures range from a frigid minimum of -17°C (1°F) to a modest maximum of 20°C (68°F), with an average of only 2°C (36°F). The month typically experiences 63 mm (2.5 in) of precipitation over about 9 days, coupled with relatively high humidity at 84%. In contrast, May showcases a substantial rise in temperatures, with a minimum of 2°C (35°F) and a maximum that can reach up to 35°C (95°F), resulting in an average of 18°C (65°F). This month is also wetter, with 133 mm (5.2 in) of precipitation spread over 14 days, and humidity levels slightly lower at 78%. For a detailed overview of the weather in May, visit Philadelphia weather in May.
In January, the weather is quite chilly, with temperatures ranging from a frigid -17°C (1°F) to a mild 20°C (68°F) and an average of 2°C (36°F). The month sees approximately 63 mm (2.5 in) of precipitation spread over 9 days, all while maintaining a high humidity level of 84%. In stark contrast, June brings warmer conditions, with temperatures starting at a minimum of 10°C (50°F) and peaking at 36°C (98°F), averaging around 23°C (74°F). Rainfall increases to 102 mm (4.0 in) over 11 days, and humidity decreases slightly to 79%. For more detailed information on the warmer months, you can check out Philadelphia weather in June.
January and July present a stark contrast in weather conditions. In January, temperatures can drop as low as -17°C (1°F), with an average of 2°C (36°F) and a maximum of 20°C (68°F). The month experiences relatively high humidity at 84%, along with 63 mm (2.5 in) of precipitation spread over 9 days. Conversely, July sees a much warmer range, with minimum temperatures around 14°C (58°F), an average of 26°C (79°F), and highs reaching up to 37°C (99°F). Although July is generally drier, it still receives significant rainfall, totaling 131 mm (5.2 in) over 13 days, and the humidity is slightly lower at 74%. This seasonal shift highlights the dramatic variations in climate experienced throughout the year. For more details, you can check Philadelphia weather in July.
January and August present stark contrasts in weather conditions. In January, temperatures can plunge as low as -17°C (1°F), with an average of 2°C (36°F) and occasional highs reaching 20°C (68°F). The month sees substantial humidity at 84%, along with 63 mm (2.5 in) of precipitation over 9 days. In contrast, August boasts much warmer temperatures, with a minimum of 14°C (58°F), an average of 25°C (77°F), and maximums that can soar to 35°C (96°F). Precipitation increases to 134 mm (5.3 in) over 14 days, but humidity is lower at 72%. This significant variance highlights the seasonal shifts in Philadelphia’s climate. For more details, you can check Philadelphia weather in August.
January and September present starkly contrasting weather conditions. In January, temperatures can plummet to a chilling minimum of -17°C (1°F), with an average of just 2°C (36°F) and a maximum that reaches 20°C (68°F). This winter month also experiences significant humidity at 84%, accompanied by 63 mm (2.5 in) of precipitation over about 9 days. Conversely, September welcomes a much milder climate, with minimum temperatures around 6°C (44°F) and an average of 22°C (71°F) soaring up to a maximum of 35°C (95°F). While September does have slightly more precipitation at 93 mm (3.7 in) over 10 days, the humidity is lower at 75%. For more details on September weather, check out Philadelphia weather in September.
January and October present stark contrasts in weather conditions. In January, temperatures can plummet to a minimum of -17°C (1°F), with an average of 2°C (36°F) and a maximum of 20°C (68°F). The month experiences 63 mm (2.5 in) of precipitation over 9 days and maintains a high humidity of 84%. In contrast, October boasts a much milder climate, with minimum temperatures starting at 2°C (37°F), an average of 16°C (61°F), and highs reaching up to 35°C (96°F). Precipitation increases to 106 mm (4.2 in) across the same number of rainy days, yet humidity remains slightly lower at 81%. For more specific details on Philadelphia's October weather, you can check Philadelphia weather in October.
January and November exhibit distinct weather patterns, with January being notably colder. In January, temperatures can plunge to a minimum of -17°C (1°F), with an average temperature of around 2°C (36°F) and a maximum reaching 20°C (68°F). In contrast, November has milder temperatures, ranging from a minimum of -8°C (18°F) to an average of 8°C (47°F), and a maximum of 25°C (77°F). Precipitation is slightly higher in November, totaling 83 mm (3.3 in) across 8 days compared to January's 63 mm (2.5 in) over 9 days, while humidity levels remain relatively similar at 84% in January and 85% in November. For more detailed information about the conditions in November, visit Philadelphia weather in November.
In comparing the weather of January and December, January tends to be slightly colder with a minimum temperature of -17°C (1°F) compared to December's minimum of -12°C (10°F). However, January's average temperature is marginally lower at 2°C (36°F), while December boasts an average of 4°C (40°F). Precipitation levels are also noteworthy; January receives 63 mm (2.5 inches) over approximately 9 days, whereas December is wetter with 100 mm (4.0 inches) spread over 10 days. Both months share a humidity level of 84%, reflecting a consistent moisture content in the air. For more details on the weather patterns specific to December, you can check out Philadelphia weather in December.
January in Philadelphia stands out as a month of contrasts, characterized by its chilly temperatures and notable precipitation. With an average temperature hovering around 2°C (36°F) and the occasional dip to a brisk -17°C (1°F), this winter month offers a stark departure from the more temperate conditions of spring and fall. The city also experiences significant humidity at 84%, contributing to a biting cold that can feel even harsher. While January features around nine days of precipitation, it brings a unique beauty to the city, often transforming the landscape into a serene winter haven. For a more comprehensive view of what to expect throughout the year, check out Philadelphia Climate.