Last updated: August 31, 2025
January in San Juan, Puerto Rico greets visitors with a pleasant tropical climate, characterized by maximum temperatures reaching 29°C (85°F) and an average of 25°C (77°F). The nights cool down to a comfortable minimum of 21°C (69°F), making it ideal for evening outings. While travelers should be prepared for some rain—averaging 38 mm (1.5 in) over 12 days—the humidity level at 76% adds to the lush, vibrant atmosphere of the island. Overall, January presents a captivating blend of warmth and delightful tropical vibes, perfect for exploring the beauty of this Caribbean paradise.
In San Juan, Puerto Rico, January temperatures offer a delightful tropical escape, with daily highs reaching a warm 29°C (85°F) and a comfortable average of 25°C (77°F). Nighttime lows drop to a mild 21°C (69°F), making it a perfect time for evening strolls along the beach. As we transition into February and March, temperatures remain consistently inviting, with similar averages and slightly increasing maximums peaking at 30°C (86°F) by March. This trend of warm, stable weather continues into the spring months, highlighting San Juan's charm as a year-round destination for sun-seekers. Whether basking in the sun or enjoying the cooler evenings, January in San Juan promises a perfect blend of warmth and comfort.
In San Juan, Puerto Rico, January marks the beginning of the year with a modest precipitation total of 38 mm (1.5 in), spread across approximately 12 rainy days. This sets the stage for a gradual increase in rainfall as the months progress; February sees a slight rise to 43 mm (1.7 in), while March’s totals jump significantly to 67 mm (2.6 in). The trend continues, peaking in September with a remarkable 173 mm (6.8 in), illustrating the island’s wettest month. Throughout this transitional period, residents can expect a steady increase in both rainfall amounts and days, reflecting the shift from the drier early months to the more humid and rain-soaked late summer and fall. This pattern of rising precipitation not only affects the lush landscapes but also underscores the importance of preparing for the wetter months ahead.
In January, San Juan experiences a humidity level of 76%, setting the stage for the island's tropical charm. This percentage is relatively typical for winter in Puerto Rico, as the climate remains consistently warm and inviting. As the months progress, a slight decline in humidity is noted, reaching its lowest point in March at 74%. However, spring transitions back to summer, bringing an uptick in moisture with June recording 77%, and peak levels of 80% in both July and August. As the year winds down, humidity levels stabilize somewhat, ending the year with a return to 76% in December. Overall, the data illustrates a gentle ebb and flow of humidity, reflective of San Juan's picturesque coastal climate.
In January, San Juan, Puerto Rico, experiences a UV Index of 9, categorizing it as very high and indicating a burn time of just 15 minutes for unprotected skin. As the months progress, this trend intensifies sharply; by February, the index spikes to 11 with an extreme exposure level, reducing burn time to a mere 10 minutes. This extreme pattern continues through March to May, when the UV Index reaches a striking 14, prompting year-round vigilance. While the index slightly dips to 12 in July and October, the month-to-month variations illustrate an overall trend of high UV exposure. Conclusively, from November back to December, the UV Index decreases to 9 and then 8, both marked as very high, suggesting that even in the year's later months, sun protection remains crucial. For more details, visit San Juan UV Index.
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In January, San Juan, Puerto Rico, basks in 257 hours of sunshine, marking the start of a bright year. As winter progresses into February and March, daylight hours increase noticeably, peaking at 346 hours in both April and March. The trend continues into May, where residents enjoy 356 hours of radiant sunshine, creating the perfect climate for outdoor activities. The sunshine remains abundant during the summer months, with July and August offering 353 and 349 hours, respectively. As the year draws to a close, daylight hours gradually decline, yet December still bathes the island in 319 hours of golden rays, ensuring that San Juan remains a sun-kissed paradise throughout the year.
In January, San Juan, Puerto Rico, enjoys a 51% chance of sunny weather, setting the stage for a pleasant start to the year. This is a moderate beginning compared to the sunnier months that follow, with February seeing a significant 70% likelihood of sunshine. Interestingly, the trend reveals a peak in early winter, where December's sun chances hover around 63% before dipping slightly in April to 49%. As spring approaches, March still boasts a healthy 64% chance of sun, providing a lovely transition into brighter days. However, the grip of summer brings a notable drop in sunlight, particularly in June with only a 24% chance. As the year progresses, it appears January offers a balanced mixture of sunshine and cloud cover, making it a delightful time for visitors seeking both warmth and the occasional reprieve from the sun.
In San Juan, Puerto Rico, January ushers in a consistent 11 hours of daylight, a pattern that continues through February. As spring approaches in March, the days begin to lengthen, reaching 12 hours of daylight and maintaining this brightness through May. The peak of summer in June and July sees a delightful surge to 13 hours of daylight, making these months ideal for outdoor activities. As summer fades into early fall, daylight gradually diminishes back to 12 hours in August and September, before returning to the familiar 11 hours by October through December. This cyclical rhythm of daylight not only enriches the island’s vibrant lifestyle but also enhances the beauty of its picturesque sunsets throughout the year.
In January, San Juan, Puerto Rico, welcomes visitors with a gentle breeze, featuring an average wind speed of 4.1 m/s (9 mph). This tranquil start to the year contrasts with the steady increase in wind speeds seen over the following months, peaking in July at 5.3 m/s (12 mph). The winds then begin to mellow as summer fades into autumn, with the sharpest decline occurring in September, where speeds drop to 3.2 m/s (7 mph). This pattern illustrates the transition from the lively trade winds of winter and spring to the calm, soothing breezes of late summer and fall, making January's winds a refreshing prelude to the vibrant weather that unfolds throughout the year.
Weather in San Juan varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in San Juan, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather between January and February, both months exhibit a remarkably consistent temperature profile with minimum temperatures at around 21°C (69°F), average temperatures at 25°C (77°F), and maximums reaching 29°C (85°F). However, February sees a slight increase in precipitation, accumulating 43 mm (1.7 in) over 12 days, compared to January's 38 mm (1.5 in), while maintaining a similar humidity level of 75% in February compared to January's 76%. For more detailed information, you can visit San Juan weather in February.
In comparing the weather of January and March, we see some similarities and slight variations. Both months maintain a minimum temperature of 21°C (69°F), with average temperatures hovering around 25°C (77°F). However, March exhibits a slightly higher maximum temperature of 30°C (86°F) compared to 29°C (85°F) in January. Precipitation is more pronounced in March, with 67 mm (2.6 in) expected over 14 days, compared to January's 38 mm (1.5 in) over 12 days. Humidity levels are fairly close, with January at 76% and March at 74%. For a more detailed look at the typical conditions in March, you can visit San Juan weather in March.
In January, the weather in San Juan features warm temperatures with a minimum of 21°C (69°F) and an average of 25°C (77°F), reaching a maximum of 29°C (85°F). The month experiences moderate rainfall, with 38 mm (1.5 in) of precipitation over 12 days and a humidity level of 76%. In contrast, April sees slightly higher temperatures, with a minimum of 22°C (71°F), an average of 26°C (78°F), and a maximum of 31°C (88°F). Precipitation also increases in April, totaling 56 mm (2.2 in) over 10 days, while humidity remains similar at 75%. For more detailed information on April's weather, you can check San Juan weather in April.
In January, the weather tends to be slightly cooler with average temperatures ranging from a minimum of 21°C (69°F) to a maximum of 29°C (85°F). The month experiences around 38 mm (1.5 in) of precipitation spread over approximately 12 days, coupled with a humidity level of 76%. In contrast, May brings warmer temperatures, with averages between a minimum of 23°C (73°F) and a peak of 32°C (90°F). This month sees increased rainfall, totaling 64 mm (2.5 in) over about 13 days, while humidity remains relatively stable at 75%. For more detailed information on May weather, you can visit San Juan weather in May.
January and June in San Juan present distinct weather patterns. In January, temperatures range from a minimum of 21°C (69°F) to a maximum of 29°C (85°F), with an average of 25°C (77°F). The month experiences about 38 mm (1.5 in) of precipitation over 12 days, while humidity hovers around 76%. In contrast, June sees warmer conditions, with temperatures ranging from a minimum of 24°C (75°F) to a maximum of 32°C (90°F), averaging 27°C (81°F). Precipitation in June increases to 68 mm (2.7 in), spread over 15 days, and humidity remains similar at 77%. For more insights into the June weather, you can check San Juan weather in June.
January and July in San Juan showcase distinct weather patterns. January experiences milder temperatures, with minimums around 21°C (69°F) and maximums reaching 29°C (85°F), accompanied by about 38 mm (1.5 in) of precipitation spread over 12 days and a humidity level of 76%. In contrast, July is warmer, with minimum temperatures starting at 24°C (76°F) and maximums climbing to 32°C (90°F). The month sees significantly higher rainfall, totaling 87 mm (3.4 in) over 18 days, and slightly increased humidity at 80%. For a more detailed look at July's weather, you can visit San Juan weather in July.
In January, the weather tends to be warm and relatively dry, with temperatures ranging from a minimum of 21°C (69°F) to a maximum of 29°C (85°F). The month experiences an average temperature of 25°C (77°F) and receives about 38 mm (1.5 in) of precipitation over approximately 12 days, contributing to a humidity level of 76%. Conversely, August sees warmer temperatures, with minimums at 24°C (76°F) and maximums reaching 32°C (90°F). The average temperature rises to 28°C (82°F), but this comes with increased rainfall, totaling around 99 mm (3.9 in) across about 18 days and slightly higher humidity at 80%. For more detailed insights, visit San Juan weather in August.
January and September in San Juan present notable differences in weather patterns. January features milder temperatures, with a minimum of 21°C (69°F) and an average of 25°C (77°F), while September boasts warmer conditions, seeing minimums around 24°C (76°F) and an average of 28°C (82°F). Precipitation is significantly higher in September, with 173 mm (6.8 in) over 23 days compared to January's 38 mm (1.5 in) spread over 12 days. Additionally, humidity levels remain consistent, with January at 76% and September slightly higher at 79%. For a more detailed overview, you can check out San Juan weather in September.
In January, the weather in San Juan tends to be warm and relatively drier, with temperatures ranging from a minimum of 21°C (69°F) to a maximum of 29°C (85°F) and an average of 25°C (77°F). The month sees about 38 mm (1.5 in) of precipitation over approximately 12 days, with humidity levels hovering around 76%. In contrast, October experiences slightly warmer temperatures, with a minimum of 24°C (75°F) and a maximum of 32°C (89°F), averaging 27°C (81°F). However, October is significantly wetter, receiving around 145 mm (5.7 in) of rain across 22 days, while humidity remains relatively high at 78%. For more detailed information, you can check San Juan weather in October.
When comparing January and November weather, January tends to be slightly cooler and drier. In January, temperatures range from a minimum of 21°C (69°F) to a maximum of 29°C (85°F), with an average of 25°C (77°F) and only 38 mm (1.5 in) of precipitation over approximately 12 rainy days. In contrast, November features warmer temperatures, with a minimum of 23°C (74°F) and a maximum of 31°C (87°F), and an average of 26°C (80°F). November also sees significantly more rainfall, with 106 mm (4.2 in) spread over about 16 days. Additionally, humidity is slightly higher in November, at 78%, compared to 76% in January. For more detailed information, check out San Juan weather in November.
In comparing the weather between January and December, January tends to be slightly cooler, with temperatures averaging around 25°C (77°F), whereas December sees a higher average of 26°C (78°F). The maximum temperatures in December can reach up to 31°C (87°F), which is warmer than January's maximum of 29°C (85°F). Additionally, December experiences more precipitation, with 51 mm (2.0 in) over 16 days compared to January's 38 mm (1.5 in) over 12 days. Both months maintain a consistent humidity level of 76%. For more detailed information on December weather, you can check San Juan weather in December.
As January unfolds in San Juan, the weather showcases a delightful blend of warmth and humidity, with average temperatures hovering pleasantly around 25°C. Unlike the hotter summer months, this time of year offers a refreshing respite, though the occasional rain may sprinkle the tropical landscape. With approximately 12 days of precipitation, the air is infused with a sense of freshness, often accompanied by the cooling island breezes. Overall, January stands out as a cooler and more temperate month, inviting visitors to bask in the beauty of San Juan without the sweltering heat of the peak season. For more insights into the city's climate, check out San Juan Climate.