Last updated: August 31, 2025
December in San Juan, Puerto Rico offers a delightful tropical climate, with maximum temperatures reaching 31°C (87°F) and an average of 26°C (78°F), perfect for beach outings. While the minimum dips to a comfortable 23°C (73°F), expect to encounter some rainfall, as the month averages 51 mm (2.0 in) of precipitation over approximately 16 days. Humidity levels hover around a balmy 76%, adding to the island's enchanting charm. Whether exploring vibrant streets or relaxing under the sun, December presents a unique blend of warmth and occasional showers that characterizes this Caribbean paradise.
In December, San Juan, Puerto Rico, experiences mild and pleasant temperatures that mark the onset of the winter season. With minimums around 23°C (73°F) and maximums peaking at 31°C (87°F), the month provides a comfortable climate for both locals and visitors. The average temperature of 26°C (78°F) offers a delightful warmth, making it an ideal time for beach outings and exploring the vibrant city. Notably, as the year winds down, December maintains similar patterns to the preceding months, showing only slight fluctuations. This stability in temperatures, paired with the festive atmosphere, makes December a particularly alluring time to soak up the sun and enjoy all that San Juan has to offer.
In December, San Juan, Puerto Rico experiences a notable shift in its precipitation patterns, with 51 mm (2.0 in) of rainfall over 16 days. This marks a significant decrease from the intense rains of September and October, which see totals of 173 mm (6.8 in) and 145 mm (5.7 in) respectively, as the island transitions away from the peak of the wet season. Although December continues to show some rainfall, the amount is more moderate compared to the earlier months, signaling the arrival of drier winter conditions. Travelers can expect occasional showers, yet the month typically offers plenty of sunny days that showcase the beauty of San Juan’s vibrant landscapes.
In December, San Juan, Puerto Rico experiences a comfortable humidity level of 76%, marking a slight decrease from the higher figures of the summer months, where humidity peaks at 80% in July and August. The latter part of the year shows a general trend of stabilization, with November and December both hovering around the mid-seventy range. As the weather transitions from the warmer, humid summer to the cooler winter months, the humidity remains relatively consistent, contributing to a pleasant tropical ambiance. This slight dip in December also hints at the gradual approach towards the cooler, drier months ahead, making it an ideal time for visitors to explore the island's vibrant culture and stunning landscapes.
As December rolls into San Juan, Puerto Rico, residents and visitors can expect a UV Index of 8, categorizing the sun's rays as very high with a recommended burn time of just 15 minutes. This marks a slight decline from the earlier months, where the index peaked at 14 in May and maintained an extreme rating throughout the summer. The monthly trend showcases a consistent intensity from February to October, where the index frequently hits extremes—reflecting the robust Caribbean sun. As the year winds down, it serves as a timely reminder that even during the holiday season, sun safety remains essential. For more insights into UV exposure, visit San Juan UV Index.
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In December, San Juan, Puerto Rico basks in a delightful 319 hours of sunshine, wrapping up the year with a radiant glow. As the winter months roll in, sunlight remains abundant, slightly dipping from the high-flying totals of the earlier months; however, it still presents a bright alternative to the winter gloom experienced elsewhere. Leading into the new year, December’s sunshine complements the trends seen from April through August, where the city enjoys near-constant high levels of warmth and light, averaging over 340 hours each month. This consistent sunny disposition not only enhances the vibrant beauty of San Juan’s beaches and historic architecture but also invites visitors to savor the island's festive atmosphere—making it a perfect escape during the holiday season.
In December, San Juan, Puerto Rico, boasts a promising 63% likelihood of sunny weather, making it an appealing month for travelers seeking warmth and sunshine. This statistic reflects the typical trend of steadily increasing sunshine as the year comes to a close, especially after the somewhat unpredictable summer months. While January begins with a modest 51% chance, December's figures suggest a delightful shift, giving way to more consistent sunny days. Coupled with the pleasant temperatures, this makes December an ideal time to enjoy the vibrant outdoor culture and stunning beaches of San Juan.
In San Juan, Puerto Rico, December marks a return to 11 hours of daylight, mirroring the shorter days of January and February. As the year progresses from spring into summer, daylight gradually increases, peaking at an impressive 13 hours in June and July. Following this bright peak, the trend shifts back down, bringing longer twilight hours in the fall with 12 hours in August and September, before settling into the shorter days of late autumn and winter. This natural ebb and flow not only guides the island's rhythm of life but also invites visitors to bask in the tropical sunshine, particularly during the more vibrant months.
As December settles over San Juan, Puerto Rico, the average wind speed picks up to a refreshing 4.4 m/s (10 mph), reflecting a pattern of steady breezes throughout the year. Following a slight dip in the fall months, where wind speeds hovered around 3.5 to 3.7 m/s, December brings a gentle uptick, reminiscent of the more spirited winds seen in the summer months, particularly in July with its peak at 5.3 m/s (12 mph). This transition highlights December’s role as a bridge between the calmer autumn season and the livelier gusts of the warmer months. The consistent breezes serve to enhance the island's tropical charm, making it an idyllic time for outdoor festivities and beach outings as the year draws to a close.
Weather in San Juan varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in San Juan, focusing on differences in temperature, rainfall, humidity, and UV levels.
The weather in December is generally warmer than in January, with December experiencing average temperatures around 26°C (78°F) and a maximum of 31°C (87°F), while January sees slightly cooler averages of 25°C (77°F) and a maximum of 29°C (85°F). December also has more rainfall, totaling 51 mm (2.0 in) over 16 days, compared to January's 38 mm (1.5 in) over 12 days. Humidity remains consistent between the two months at 76%. For more detailed information, you can check San Juan weather in January.
In December, the weather is typically warmer, with temperatures ranging from a minimum of 23°C (73°F) to a maximum of 31°C (87°F) and an average of 26°C (78°F). This month experiences higher precipitation, totaling 51 mm (2.0 in) over approximately 16 days, and features a humidity level of 76%. In contrast, February presents slightly cooler temperatures, with a minimum of 21°C (70°F), an average of 25°C (77°F), and a maximum of 29°C (85°F). Precipitation decreases to 43 mm (1.7 in) across about 12 days, while humidity remains fairly consistent at 75%. For more details on what to expect, check out San Juan weather in February.
December and March showcase similar warm temperatures, with December averaging a slightly higher max of 31°C (87°F) compared to March's 30°C (86°F). However, December tends to be a bit wetter, receiving 51 mm (2.0 in) of precipitation over 16 days, while March sees 67 mm (2.6 in) across 14 days. Both months have high humidity levels, with December at 76% and March at 74%, creating a tropical feel throughout this period. For a detailed look at March’s weather, you can check San Juan weather in March.
In comparing the weather between December and April, both months have similar average temperatures, with December having a minimum of 23°C (73°F) and April slightly lower at 22°C (71°F). Both months peak at around 31°C (87-88°F), providing a warm and inviting climate. December experiences a bit more rainfall, with 51 mm (2.0 in) over 16 days, while April sees slightly higher precipitation at 56 mm (2.2 in) but over just 10 days. Additionally, humidity levels are comparable, with December at 76% and April at 75%. For more detailed information on April weather, you can visit San Juan weather in April.
In comparing the weather between December and May, both months exhibit warm and humid conditions typical of tropical climates. December sees average temperatures ranging from a minimum of 23°C (73°F) to a maximum of 31°C (87°F), with an average of 26°C (78°F). This month experiences approximately 51 mm (2.0 in) of precipitation over 16 days, resulting in a humidity level of 76%. In contrast, May has slightly higher average temperatures, with minimums still at 23°C (73°F) but reaching up to 32°C (90°F) for its maximum, making the average temperature 27°C (80°F). May also has increased precipitation at 64 mm (2.5 in) but fewer rainy days, totaling only 13, and it maintains a similar humidity level at 75%. For a detailed look at May weather specifically, you can check San Juan weather in May.
In December, temperatures range from a minimum of 23°C (73°F) to a maximum of 31°C (87°F), with an average of 26°C (78°F). The month experiences 51 mm (2.0 in) of precipitation over 16 days, contributing to a relatively humid environment at 76%. In contrast, June sees slightly warmer temperatures, with a minimum of 24°C (75°F) and a maximum of 32°C (90°F), averaging 27°C (81°F). Precipitation increases to 68 mm (2.7 in) over 15 days, while humidity remains slightly higher at 77%. To explore more about the June weather specifics, you can follow this link: San Juan weather in June.
In comparing the weather of December and July, December tends to be slightly cooler, with average temperatures ranging from a minimum of 23°C (73°F) to a maximum of 31°C (87°F), while July offers warmer conditions with a minimum of 24°C (76°F) and a maximum reaching 32°C (90°F). Additionally, July experiences more precipitation, totaling 87 mm (3.4 in) over 18 days compared to December's 51 mm (2.0 in) over 16 days. Humidity levels remain high in both months, with July at 80% and December at 76%. For a detailed look at July's weather conditions, you can visit San Juan weather in July.
In December, San Juan experiences slightly cooler temperatures with a minimum of 23°C (73°F) and an average of 26°C (78°F), peaking at 31°C (87°F). The month sees about 51 mm (2.0 in) of precipitation over 16 days, with humidity levels averaging 76%. In contrast, August is warmer, featuring a minimum temperature of 24°C (76°F) and an average of 28°C (82°F), reaching a maximum of 32°C (90°F). August is also wetter, with 99 mm (3.9 in) of rain spread over 18 days and a slightly higher humidity of 80%. For a deeper dive into August weather specifics, you can refer to San Juan weather in August.
In comparing the weather between December and September, December tends to be slightly cooler, with an average temperature of 26°C (78°F) and a maximum of 31°C (87°F), while September boasts a warmer average of 28°C (82°F) and a maximum of 32°C (90°F). Precipitation levels in September are notably higher, totaling 173 mm (6.8 in) over 23 days compared to December's 51 mm (2.0 in) over 16 days. Humidity remains relatively high in both months, with December at 76% and September at 79%. For more insights, visit San Juan weather in September.
In comparing the weather between December and October, December tends to be slightly cooler, with average temperatures ranging from a minimum of 23°C (73°F) to a maximum of 31°C (87°F), while October features slightly warmer conditions with a minimum of 24°C (75°F) and a maximum of 32°C (89°F). Precipitation is significantly higher in October, accumulating 145 mm (5.7 in) over 22 days compared to December's 51 mm (2.0 in) over 16 days. Humidity remains fairly consistent, with December at 76% and October at 78%. For more detailed information, you can check out San Juan weather in October.
In comparing the weather between December and November, both months exhibit similar temperature ranges, with minimums at 23°C (73°F), averages around 26°C (78°F), and maximums reaching 31°C (87°F). However, December tends to be drier, with a total precipitation of 51 mm (2.0 inches) compared to November's 106 mm (4.2 inches), despite having the same number of rainy days at 16. Additionally, humidity decreases slightly in December to 76%, down from November's 78%. For more details on the weather specifics in November, check out San Juan weather in November.
As December sets in, San Juan’s weather offers a delightful shift that distinguishes it from the hotter summer months. With pleasant temperatures averaging around 26°C (78°F), the city welcomes a more comfortable warmth that invites outdoor exploration. However, the increase in precipitation, totaling 51 mm (2.0 in) over about half the month, adds a refreshing contrast to the typical dry heat. While the humidity lingers at 76%, the cooler breezes provide relief, making December an ideal time to experience the beauty of San Juan’s festive atmosphere. For more insights into what to expect throughout the year, check out the San Juan Climate.