Last updated: February 24, 2025
In January, Port Jefferson experiences a chill in the air with an average temperature around 2°C (35°F), complemented by maximum highs of 15°C (60°F) and dipping lows to a brisk -15°C (6°F). The month is characterized by notable precipitation, with approximately 80 mm (3.1 in) falling over 8 days, contributing to a substantial humidity level of 84%. This blend of cold temperatures and moisture creates a distinct winter atmosphere, ideal for those seeking a true seasonal experience.
In Port Jefferson, January offers a frigid tapestry of winter weather, where temperatures can dip as low as -15°C (6°F), yet can reach a surprisingly mild 15°C (60°F) on warmer days. The average temperature hovers around 2°C (35°F), suggesting a month characterized by stark contrasts. This chill sets the stage for the transition into February, which mirrors January's temperature profile. As winter progresses into March, a slight elevation in warmth emerges, with average temperatures rising to 4°C (40°F) and potential highs of 19°C (67°F), hinting at the impending arrival of spring. The gradual change in temperatures not only reflects the seasonal shift but also invites residents and visitors alike to embrace the seasonal beauty that Port Jefferson has to offer, from the crisp air of January to the tentative warmth of spring.
In January, Port Jefferson experiences an average precipitation of 80 mm (3.1 in), with rain falling on approximately 8 days. This initial month sets the stage for a trend of increasing precipitation as the year progresses; February sees a jump to 112 mm and 12 days of rainfall. The wettest month arrives in April, with 132 mm (5.2 in) recorded, hinting at the impending spring burst of life. Throughout the year, precipitation remains relatively consistent, peaking in October at 143 mm (5.6 in), just as the fall foliage covers the area in vibrant colors. On average, the winter months of January and February tend to be drier, contrasting with the spring and fall months, which typically bring heavier and more frequent rainfall, shaping the lush landscape of Port Jefferson.
In January, Port Jefferson experiences its highest humidity level at 84%, setting the tone for a damp winter. This high moisture content gradually decreases as the year progresses, with February and March following closely at 82% and 81%, respectively. By the time we reach April, humidity drops further to 78%, ushering in more comfortable spring weather. As temperatures rise in May and June, humidity stabilizes around 69%, signifying a transition to summer. The warmest months, July and August, see a slight increase to 62% and 65%, offering a reprieve from excessive dampness. However, as autumn sets in, humidity climbs back up, peaking at 82% in November before settling at 80% in December. This cyclical trend underscores Port Jefferson's characteristic, humid winters and balanced summers, inviting both cozy indoor gatherings and refreshing outdoor activities year-round.
In January, Port Jefferson experiences a moderate UV Index of 3, indicating that while sun exposure is safe for most, precautions are still advisable. With a burn time of around 30 minutes, it’s essential to plan your outdoor activities with care, especially as the UV Index begins to rise in the following months. By February, the UV Index increases to 5, and by March, it reaches a high of 6, prompting a decrease in burn time to 25 minutes. As spring transitions into summer, the UV Index peaks in May and June at a striking 10, categorizing the risk as very high and shortening burn time dramatically to just 15 minutes. This trend continues through the summer months, with August and September maintaining high levels before gradually tapering off in the fall. As the winter approaches again, the UV Index decreases, offering a reprieve with a low value of 2 in December. For more detailed insights on UV exposure, visit Port Jefferson UV Index.
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In January, Port Jefferson greets the new year with a modest 154 hours of sunshine, a gentle reminder of winter's embrace. As the days lengthen, February sees an increase to 180 hours, hinting at the promise of spring. By March, the sun fully asserts itself, pouring in 258 hours of golden rays, which paves the way for the lively April with 246 hours. The warmth intensifies in May and June, with sunshine peaking at 285 and 319 hours, respectively, drawing residents outdoors to enjoy the vibrant bloom. Summer reaches its zenith in July with the year’s maximum of 343 hours, radiating joy and activity, before mellowing slightly in August. As autumn approaches, sunshine begins to ebb, with September offering 282 hours and a more subdued circulation that continues through October and November. Finally, December wraps up the year with a cozy 176 hours. This trend of increasing sunshine from winter to summer, followed by a gradual descent back into the gloom, beautifully illustrates the seasonal rhythm of Port Jefferson, where each month holds its own unique charm.
In Port Jefferson, the likelihood of enjoying sunny weather in January stands at a noteworthy 52%, making it one of the more favorable months for sunshine in the winter season. This chance is notably higher than the subsequent month of February, which drops to 31%, and is also a critical lead-in to the more sunlit days of March at 58%. Interestingly, January's sunny possibility is comparable to the averages seen in the spring months, with April at 48%. As we analyze the yearly trends, it becomes evident that while winter often brings cloudier days, January offers a glimmer of hope for sun seekers, providing a decent chance to bask in sunlight amidst the cold.
In Port Jefferson, United States, January brings a modest 9 hours of daylight, setting the stage for a gradual increase in sunlight as the months progress. As winter fades into spring, February sees daylight extend to 10 hours and March boasts 11 hours, signaling the sun's return with longer, brighter days. By April, daylight reaches 13 hours, and it peaks in June at 15 hours, inviting outdoor activities and longer evenings. In July, daylight slightly decreases to 14 hours, followed by a gradual decline through August and September, ultimately returning to the 9 hours observed in November and December. This clear trend of increasing daylight leading into the summer months and gentle tapering towards winter reflects the natural rhythm of the seasons, enriching the local experience and lifestyle throughout the year.
In Port Jefferson, January brings a refreshing average wind speed of 5.0 m/s (11 mph), making it one of the windiest months of the year. As winter transitions into spring, wind speeds gradually decline, with February and March maintaining the same brisk pace but dipping slightly to 4.9 m/s. By April, the winds mellow even further, averaging 4.4 m/s, and continue to ease through the warmer months, hitting a low of 3.4 m/s (8 mph) in both July and August. This seasonal cycle highlights a consistent pattern where winter winds blow more vigorously, while the summer months offer a gentler breeze, before a slight uptick returns in the fall, culminating at 4.7 m/s in October. Overall, January sets the tone for a dynamic wind environment that varies beautifully throughout the year.
The weather in Port Jefferson 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 Port Jefferson and find detailed weather information for every month.
January and February in Port Jefferson exhibit similar temperature ranges, with both months experiencing minimum temperatures as low as -15°C (6°F) and average highs around 2°C (35°F) to 15°C (60°F). However, February tends to be slightly wetter, with precipitation totaling 112 mm (4.4 in) spread over 12 days, compared to January's 80 mm (3.1 in) over 8 days. Interestingly, while the humidity levels remain relatively close, February's humidity is marginally lower at 82%, as opposed to January's 84%. For more detailed insights, you can check the Port Jefferson weather in February.
In January, temperatures typically range from a chilly -15°C (6°F) as a minimum to a milder 15°C (60°F) at their warmest, averaging around 2°C (35°F). The month experiences about 80 mm (3.1 in) of precipitation over roughly 8 days, coupled with a high humidity level of 84%. In contrast, March brings a noticeable warming trend with minimum temperatures around -8°C (17°F) and maximums reaching 19°C (67°F), averaging 4°C (40°F). March also sees an increase in precipitation to 104 mm (4.1 in) over approximately 10 days, while humidity slightly decreases to 81%. For more detailed information on March weather in Port Jefferson, visit Port Jefferson weather in March.
In January, temperatures can plunge as low as -15°C (6°F), with an average of around 2°C (35°F) and highs reaching up to 15°C (60°F). The month experiences about 80 mm (3.1 in) of precipitation over approximately 8 days, coupled with a high humidity level of 84%. In contrast, April brings a notable warming trend with minimum temperatures of -1°C (31°F) and averaging 9°C (49°F), while reaching a maximum of 22°C (71°F). However, April is wetter, with 132 mm (5.2 in) of precipitation over about 12 days and slightly lower humidity at 78%. For more detailed insights, you can explore Port Jefferson weather in April.
In January, the weather is typically quite cold, with temperatures ranging from a frigid minimum of -15°C (6°F) to a mild maximum of 15°C (60°F), averaging around 2°C (35°F). The month experiences about 80 mm (3.1 in) of precipitation over 8 days, accompanied by high humidity at 84%. In contrast, May brings a significant shift in climate, with temperatures rising considerably; the minimum is 3°C (37°F) and the maximum reaches 26°C (79°F), averaging 14°C (58°F). Precipitation also increases slightly to 119 mm (4.7 in) over 13 days, but humidity drops to a more comfortable 69%. This transition from the harsh winter chill to the warmer, more pleasant spring conditions can be stark. For a detailed look at what to expect, check out Port Jefferson weather in May.
January and June present a striking contrast in weather characteristics. In January, temperatures can plummet as low as -15°C (6°F), while averaging around 2°C (35°F) and reaching a maximum of 15°C (60°F). The month sees substantial precipitation, with about 80 mm (3.1 in) falling over 8 days, accompanied by high humidity levels of 84%. On the other hand, June offers a much milder climate with temperatures ranging from a minimum of 10°C (50°F) to an average of 20°C (68°F) and peaking at 29°C (85°F). Despite slightly higher precipitation at 87 mm (3.4 in) and rain occurring over 9 days, the humidity decreases to a more comfortable 69%. For more details, check Port Jefferson weather in June.
The weather in January contrasts sharply with that in July. In January, temperatures range from a chilly -15°C (6°F) to a mild 15°C (60°F), with an average around 2°C (35°F). The month sees significant humidity levels at 84% and experiences about 80 mm (3.1 in) of precipitation over 8 days. Conversely, July presents a warm and inviting climate, with temperatures spanning from a minimum of 16°C (60°F) to a maximum of 33°C (91°F), averaging around 24°C (76°F). Although July enjoys slightly more precipitation at 131 mm (5.2 in) over 12 days, the humidity drops to a more comfortable 62%. For a detailed look at July weather in Port Jefferson, visit Port Jefferson weather in July.
The weather in January and August presents a stark contrast. In January, temperatures can drop as low as -15°C (6°F), with an average of 2°C (35°F) and a maximum reaching 15°C (60°F). This month also experiences high humidity at 84% and about 80 mm (3.1 in) of precipitation over 8 days. In contrast, August boasts much warmer temperatures, with minimums of 16°C (61°F), averages around 24°C (75°F), and maxes hitting 31°C (88°F). Although August sees slightly more precipitation at 103 mm (4.0 in) over 11 days, the humidity is considerably lower at 65%. For more detailed information about August weather, you can visit Port Jefferson weather in August.
January and September present stark contrasts in weather. In January, temperatures can plummet to a minimum of -15°C (6°F) and average around 2°C (35°F), while September enjoys much milder conditions with lows of 11°C (52°F) and an average of 21°C (70°F). The maximum temperature in January reaches only 15°C (60°F), but September peaks at a warm 30°C (87°F). Additionally, January sees about 80 mm (3.1 in) of precipitation spread over 8 days, whereas September experiences a slightly higher precipitation level of 94 mm (3.7 in) across 10 days. Humidity is also higher in January at 84%, compared to a more comfortable 68% in September. For a deeper insight into September weather specifics, you can visit Port Jefferson weather in September.
January and October exhibit stark contrasts in weather conditions. January is marked by much colder temperatures, with a minimum of -15°C (6°F) and an average near freezing at 2°C (35°F), while October enjoys milder temperatures, ranging from a minimum of 5°C (41°F) to a pleasant average of 16°C (61°F). Additionally, January experiences lower precipitation levels, totaling 80 mm (3.1 in) over approximately 8 days, compared to October's wetter climate, which sees 143 mm (5.6 in) over around 12 days. While January has a higher humidity level of 84%, October's humidity is relatively lower at 74%. For more specifics on October weather, you can refer to Port Jefferson weather in October.
When comparing the weather in January and November, notable differences emerge. January is generally colder, with temperatures ranging from a minimum of -15°C (6°F) to a maximum of 15°C (60°F), averaging around 2°C (35°F). In contrast, November enjoys milder conditions, with minimum temperatures of -6°C (21°F) and maximums reaching 21°C (70°F), averaging 9°C (49°F). Precipitation is slightly higher in November at 103 mm (4.0 in) over 9 days, compared to January's 80 mm (3.1 in) over 8 days. Additionally, January tends to feel more humid at 84%, while November maintains a slightly lower humidity level of 82%. For more insights into November weather, you can check Port Jefferson weather in November.
In January, the weather tends to be colder than in December, with minimum temperatures dropping to -15°C (6°F) compared to December's minimum of -10°C (15°F). The average temperature in January is around 2°C (35°F), slightly cooler than December's 5°C (40°F). Additionally, January experiences less precipitation, totaling 80 mm (3.1 in) over 8 days, whereas December sees more rain, accumulating 140 mm (5.5 in) over 11 days. The humidity levels are relatively similar, with January at 84% and December at 80%. For a more detailed look at the weather in December, you can visit Port Jefferson weather in December.
January in Port Jefferson showcases a dramatic contrast to the milder months of the year. With frigid temperatures that can dip to -15°C (6°F), this month stands out for its chilly embrace, making it the coldest time of year. The average temperature hovers around 2°C (35°F), while occasional peaks reach up to 15°C (60°F), offering fleeting moments of warmth amidst the winter chill. January also brings an increase in precipitation, with about eight days of rain or snow contributing to a humidity level of 84%, enhancing the winter atmosphere. For a deeper understanding of the seasonal shifts, visit Port Jefferson Climate.