Last updated: August 31, 2025
December in Guaynabo, Puerto Rico offers a delightful tropical experience characterized by warm temperatures and high humidity. With a maximum temperature reaching 30°C (86°F) and an average of 25°C (77°F), the weather is pleasantly mild, although nights can cool down to a minimum of 21°C (71°F). Visitors can anticipate about 66 mm (2.6 in) of rain across approximately 22 days, providing a refreshing backdrop for holiday festivities. The prevailing humidity level of 76% adds to the tropical ambiance, making it a perfect time to explore the lush landscapes and vibrant culture of this beautiful region.
In Guaynabo, Puerto Rico, December offers a pleasant climate as temperatures begin to cool slightly from the warmer months. With minimums around 21°C (71°F), averages at 25°C (77°F), and maximums reaching 30°C (86°F), the month shows a mild transition towards the cooler season. This pattern reflects a gradual dip in temperature from the previous months, maintaining a comfortable warmth typical of the tropical environment. As holiday festivities begin, residents and visitors alike can enjoy the combination of sunny days and cooler evenings, making December an ideal time to experience the vibrant culture of Guaynabo while soaking in the beautiful atmosphere.
In December, Guaynabo, Puerto Rico, typically experiences a moderate decline in precipitation with 66 mm (2.6 in) of rain spread over 22 days. This marks a noticeable drop from the heavier rainfall seen in September (200 mm) and October (183 mm), suggesting the transition from the wetter months of the year toward a drier climate. While December still retains a fair amount of rain, it’s comparatively lighter than the peak summer and early fall months, making it a more pleasant time for outdoor activities. The trend indicates that as the year winds down, Guaynabo's weather shifts towards a milder, more manageable rainy season, offering a refreshing respite from the intense storms of late summer.
In Guaynabo, Puerto Rico, December marks a subtle transition in humidity levels, showcasing a reading of 76%. This figure reflects a slight dip from the higher humidity witnessed in the warmer summer months, where July and August peaked at 80%. As the year progresses from the sweltering heat of mid-summer toward the cooler winter season, the humidity levels gradually decrease but remain relatively high throughout the year. Notably, the continuous fluctuation around the 75% to 80% range underscores the tropical climate's influence, ensuring that even in the cooler months, the air retains a noticeably moist quality that defines the region's weather patterns.
In December, Guaynabo, Puerto Rico experiences a UV Index of 8, categorized as very high with a burn time of just 15 minutes. This marks a slight decrease from the extreme levels seen in the peak months from February to September, where the UV Index ranged from 12 to 14 and burn times were consistently low at 10 minutes. As the year winds down, the intensity of UV radiation diminishes, yet the risk remains significant, especially for those spending extended time outdoors without proper protection. Notably, January also sees a return to a very high category with an index of 9. For the latest insights on UV exposure in the region, check out Guaynabo UV Index.
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As December unfolds in Guaynabo, Puerto Rico, residents and visitors alike can bask in the warmth of an impressive 319 hours of sunshine. This month shines brightly in comparison to the preceding November, which offered 299 hours, marking a notable increase in radiant days. Looking back over the year, December continues a trend of abundant sunlight that peaks in May with 356 hours and maintains a steady presence throughout most months. With sunshine hours gradually declining from early summer yet remaining robust, December encapsulates the island's tropical charm, inviting everyone to enjoy the outdoors amidst the rich, sun-kissed landscape of Puerto Rico.
In Guaynabo, Puerto Rico, the chances of enjoying sunny weather in December stand at 58%, marking a notable increase as the year draws to a close. While the earlier months of February and March boast higher probabilities of sun, December offers a favorable balance with its almost 60% likelihood, particularly following the wetter months of the summer. November's 55% likelihood sets a promising stage, and December continues that trend of improving sunshine as winter approaches. This makes December an optimal time to bask in the warmth and beauty of Puerto Rico's coastal charm.
In Guaynabo, Puerto Rico, December brings a seasonal echo of daylight, consistent with the preceding months, offering 11 hours of sunshine each day. This marks the conclusion of a gradual transition from the longer days of summer, where residents enjoyed up to 13 hours in June and July. As the year winds down, daylight begins to recede, shifting back to 12 hours in the spring months of March through May and finally settling at 11 hours again by November. This rhythm of daylight reveals an interesting trend: while Guaynabo experiences a moderate variation throughout the year, the back-to-back months of 11 hours reflect a cozy, consistent charm perfect for embracing the holiday spirit in the tropics.
In December, Guaynabo, Puerto Rico, experiences a refreshing shift in wind patterns with an average wind speed of 3.3 m/s (7 mph), laying comfortably between the calming breezes of earlier months and the brisk currents expected in the new year. As temperatures cool from the warmer summer months—where speeds peak at 4.0 m/s (9 mph) in both July and February—December offers a pleasant stability with wind speeds reminiscent of the pleasant January breezes. While the month may not boast the highest gusts, it does provide a consistent romanticism in the air, fostering the enchanting atmosphere that accompanies this festive season. As the year winds down, the gentle gusts remind residents and visitors alike of the beauty found in Guaynabo's tropical climate.
Weather in Guaynabo varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Guaynabo, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, the weather remains warm, with temperatures ranging from a minimum of 21°C (71°F) to a maximum of 30°C (86°F), averaging around 25°C (77°F). This month typically sees about 66 mm (2.6 in) of precipitation over 22 days, with humidity levels consistently high at 76%. In contrast, January experiences slightly cooler temperatures, with a minimum of 19°C (66°F) and a maximum of 29°C (84°F), averaging 24°C (76°F). Additionally, January has reduced rainfall, totaling 48 mm (1.9 in) over 16 days, while maintaining the same humidity level of 76%. For more detailed information, you can visit Guaynabo weather in January.
In December, the weather features slightly warmer temperatures, with minimums averaging 21°C (71°F) and maximums reaching up to 30°C (86°F). The month experiences considerable rainfall, with 66 mm (2.6 in) of precipitation over 22 days and a humidity level of 76%. In contrast, February sees a minor decrease in temperatures, with a minimum of 20°C (69°F) and a maximum of 28°C (83°F). Rainfall also decreases to 53 mm (2.1 in) across 18 days, while humidity remains relatively stable at 75%. For more detailed information on February weather, you can visit Guaynabo weather in February.
In December, the weather typically features a minimum temperature of 21°C (71°F) and an average of 25°C (77°F), peaking at a maximum of 30°C (86°F). During this month, precipitation is significant, totaling 66 mm (2.6 in) over 22 days, with a humidity level of 76%. In contrast, March experiences slightly cooler temperatures, with a minimum of 20°C (69°F) and an average of 24°C (76°F), reaching a maximum of 29°C (85°F). Additionally, March sees a bit more precipitation, averaging 80 mm (3.2 in) over 21 days, while humidity is slightly lower at 74%. For a more detailed look at the weather in March, you can visit Guaynabo weather in March.
In comparing the weather between December and April, both months share similar temperature ranges, with a minimum of 21°C (70°F), an average of 25°C (77°F), and a maximum of 30°C (86°F). However, April experiences slightly higher precipitation, totaling 77 mm (3.0 in) over 20 days, compared to December's 66 mm (2.6 in) over 22 days. Humidity levels are also comparable, with December at 76% and April slightly lower at 75%. For more detailed insights, visit Guaynabo weather in April.
In comparing the weather of December and May, both months feature warm temperatures, with December having a minimum of 21°C (71°F) and an average of 25°C (77°F), while May sees slightly higher temperatures, starting at a minimum of 22°C (72°F) and averaging 26°C (79°F). The maximum temperatures also reflect this trend, with December reaching up to 30°C (86°F) and May peaking at 31°C (87°F). Precipitation is more pronounced in May, totaling 98 mm (3.9 in) over 24 days, compared to December's 66 mm (2.6 in) across 22 days, indicating that May is generally wetter. Humidity levels are quite similar, with December at 76% and May at 75%. For more detailed information, you can check Guaynabo weather in May.
In December, the weather is generally warm, with a minimum temperature of 21°C (71°F) and an average of 25°C (77°F), peaking at 30°C (86°F). The month experiences moderate rainfall, totaling 66 mm (2.6 in) over 22 days, while humidity hovers around 76%. In contrast, June is slightly warmer, featuring a minimum temperature of 23°C (74°F) and an average of 27°C (80°F), reaching a maximum of 31°C (88°F). June is also rainier, with precipitation amounting to 99 mm (3.9 in) across 23 days and a marginally higher humidity at 77%. For more details on June weather, you can refer to Guaynabo weather in June.
In December, the weather is warm, with temperatures ranging from a minimum of 21°C (71°F) to a pleasant average of 25°C (77°F) and a maximum of 30°C (86°F). The month sees a fair amount of precipitation, totaling 66 mm (2.6 in) over 22 days, and humidity levels hover around 76%. In contrast, July experiences slightly higher temperatures, with a minimum of 23°C (74°F), an average of 27°C (81°F), and a maximum of 31°C (88°F). It also grows wetter, receiving 124 mm (4.9 in) of rain across 24 days, accompanied by increased humidity at 80%. For a more detailed look at the July weather specifics, you can visit Guaynabo weather in July.
December and August present distinct weather patterns. December boasts a slightly lower average temperature, ranging from a minimum of 21°C (71°F) to a maximum of 30°C (86°F), with an average of 25°C (77°F). In contrast, August experiences warmer conditions, with temperatures ranging from a minimum of 23°C (74°F) to a maximum of 31°C (89°F), averaging 27°C (81°F). Precipitation in December is moderate at 66 mm (2.6 in) over 22 days, while August sees significantly higher rainfall, totaling 130 mm (5.1 in) across 25 days. Additionally, humidity levels are slightly elevated in August at 80% compared to December’s 76%. For more detailed information, check Guaynabo weather in August.
In comparing the weather of December and September, we find that December generally experiences slightly lower temperatures, with an average of 25°C (77°F) compared to September’s average of 27°C (81°F). The maximum temperatures in December reach up to 30°C (86°F), while September can peak at 32°C (90°F). However, September is notably wetter, with a significant rainfall of 200 mm (7.9 in) over 27 days, compared to December’s 66 mm (2.6 in) over 22 days. Despite the lower precipitation in December, humidity levels remain high at 76%, just slightly below September's 79%. For more detailed insights into September weather, you can visit Guaynabo weather in September.
In comparing December and October, December typically exhibits slightly cooler temperatures, with a minimum of 21°C (71°F) and an average of 25°C (77°F), while October maintains higher temperatures, ranging from a minimum of 23°C (74°F) to an average of 27°C (80°F). Additionally, October experiences significantly more rainfall, with 183 mm (7.2 in) over 27 days compared to December’s 66 mm (2.6 in) over 22 days. Humidity levels are relatively similar, with December at 76% and October slightly higher at 78%. For more details, you can check out Guaynabo weather in October.
When comparing the weather in December to November, we see some notable differences. In December, the temperatures are slightly lower, with a minimum of 21°C (71°F) and an average of 25°C (77°F), while November boasts a minimum of 22°C (72°F) and a higher average of 26°C (79°F). Both months reach the same maximum temperature of 30°C (86°F). Additionally, December experiences less precipitation, totaling 66 mm (2.6 in) over 22 days, compared to November's significantly wetter conditions with 120 mm (4.7 in) over 23 days. Humidity levels are similar, hovering at 76% in December and 78% in November. For a more detailed look at November's weather, check out Guaynabo weather in November.
December in Guaynabo marks a shift in the weather pattern as temperatures become more moderate, inviting a pleasant atmosphere perfect for outdoor activities. With average highs around 25°C (77°F) and a comfortable level of humidity at 76%, the month offers a refreshing break from the heat of the preceding summer months. However, be prepared for increased rainfall, as December experiences a notable rise in precipitation, with rain falling on about 22 days and accumulating to 66 mm (2.6 in). This combination of warmth and occasional showers creates a vibrant, lush landscape, making it a special time to explore the area's natural beauty. For a comprehensive overview of what to expect throughout the year, visit Guaynabo Climate.