Last updated: August 31, 2025
September in Monserrate, Puerto Rico offers a warm tropical climate characterized by maximum temperatures peaking at 32°C (90°F) and an average of 28°C (82°F). The nights are pleasantly mild, with temperatures dipping to a minimum of 25°C (77°F). This month is also marked by significant precipitation, totaling 172 mm (6.8 in) over about 23 days, contributing to the lush landscapes of the region. With an average humidity level of 79%, visitors can expect a humid yet vibrant environment, making September a lush, albeit rainy, time to explore the beauty of Monserrate.
In September, Monserrate, Puerto Rico experiences warm and welcoming temperatures that continue the trend of the previous summer months. With minimums around 25°C (77°F) and averages hitting 28°C (82°F), the weather remains pleasantly tropical. Highs can reach a balmy 32°C (90°F), making it perfect for beachgoers and outdoor enthusiasts. This month marks a subtle transition towards cooler autumn temperatures; nevertheless, the warmth persists, ensuring that visitors can still enjoy the vibrant island landscape and lively local culture. As the summer heat begins to ebb, September offers a delightful balance of sunny days and inviting evenings.
In September, Monserrate, Puerto Rico, experiences a dramatic surge in precipitation, with 172 mm (6.8 in) of rainfall, making it one of the wettest months of the year. This significant increase in precipitation is accompanied by 23 rainy days, the highest number recorded throughout the year, indicating a notable shift as tropical storms and weather patterns intensify. Following August, which already saw a substantial 86 mm (3.4 in), September's precipitation underscores a seasonal trend of increasing rainfall during this time. As the wet season peaks, the lush landscape thrives, showcasing nature's resilience and beauty amidst the deluge.
In September, Monserrate, Puerto Rico experiences a humidity level of 79%, a slight dip from the higher peaks of 80% in both July and August. This month's humidity reflects a pattern of seasonal fluctuation that typically sees the region's levels peak in the summer months. Following September, the humidity begins to gradually decrease, settling at 78% in October and November, before closing the year back at a more moderate 76% in December. Overall, the data suggests a consistent warm and humid climate, characteristic of tropical environments, while showcasing the slight easing of moisture content as the island transitions into the cooler months.
In September, Monserrate, Puerto Rico, continues to bask under intense sun, maintaining a UV Index of 13, categorized as extreme. This level of UV exposure reflects a consistent trend observed from April through October, where residents and visitors alike should be mindful of their sun safety. With a burn time of just 10 minutes, it's crucial to take proper precautions during this month, just as one would throughout the summer. Interestingly, as the year shifts towards autumn, the UV Index remains elevated, only starting to decline in October. For more detailed information, you can check the Monserrate UV Index.
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As September rolls in, Monserrate, Puerto Rico continues to bask in an impressive 311 hours of sunshine, marking a shift from the peak brightness of summer. While the exuberance of May shines brightest with 356 hours, September still holds its own, offering a comforting warmth before the cooler months. The sun-drenched days of July and August, with 354 and 350 hours respectively, make way for a slight dip, illustrating a gradual transition to fall. The overall trend reveals a sunny consistency, demonstrating that even as summer wanes, the charm of Monserrate's golden rays remains ever-present, inviting travelers to enjoy the beauty of sun-soaked days amid the approaching autumn.
In Monserrate, Puerto Rico, September presents a 48% chance of sunny weather, placing it in the lower tier of the year’s sunshine likelihood. As summer transitions into fall, the sun tends to shy away, resulting in cloudier skies compared to the sunnier months of February and March, which boast chances exceeding 60%. This trend indicates that while September may not be the sunniest month, it still holds its own against the earlier summer months, where sunshine probabilities dip sharply in June and July. As the seasons change, those visiting in September can expect a mix of sun and clouds, providing a delightful backdrop for their tropical adventures.
In Monserrate, Puerto Rico, the daylight duration showcases a captivating rhythm throughout the year. As the year begins, January and February greet us with a consistent 11 hours of daylight. By March through May, this increases slightly, reaching a peak of 12 hours, ideal for enjoying the beautiful coastal landscapes. The summer months of June and July bask in the longest daylight, with 13 hours that invite outdoor adventures. However, as we transition into August and September, daylight returns to 12 hours, offering a perfect balance as the vibrant summer fades. Finally, the year wraps up with October through December dwindling back to 11 hours, inviting a reflective close to the cycle of daylight. This gentle ebb and flow of light guides residents and visitors alike, enhancing the natural beauty of Monserrate throughout the seasons.
As summer fades into autumn, September in Monserrate, Puerto Rico witnesses a notable drop in wind speed, averaging 3.2 m/s (7 mph)—the year's lowest. This gentle breeze marks a transition from the more robust gusts of summer, where July and August boasted average speeds of 5.3 m/s (12 mph) and 4.7 m/s (11 mph), respectively. Following the trend of diminishing winds, October and November will see only slight increases, with speeds of 3.4 m/s (8 mph) and 3.7 m/s (8 mph). This time of year offers a calm and serene atmosphere, perfect for enjoying the breathtaking views of the lush landscapes without the distraction of stronger winds.
Weather in Monserrate varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Monserrate, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather tends to be quite warm, with average temperatures reaching around 28°C (82°F) and maximums climbing up to 32°C (90°F). The month is also marked by significant rainfall, totaling 172 mm (6.8 in) over 23 days, and a high humidity level of 79%. In contrast, January offers a more temperate climate, with average temperatures dropping to 25°C (77°F) and maximum highs of 30°C (86°F). Precipitation is considerably lower, at 39 mm (1.5 in) over just 12 days, and humidity falls slightly to 76%. For more detailed insights on the January weather in Monserrate, you can visit Monserrate weather in January.
September and February exhibit notable differences in weather patterns. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 32°C (90°F), with an average of 28°C (82°F). This month is characterized by heavy rainfall, totaling 172 mm (6.8 inches) over 23 days, and high humidity levels of 79%. In contrast, February features milder conditions, with temperatures ranging from 21°C (70°F) to 30°C (85°F) and an average of 25°C (77°F). Precipitation in February is significantly lower, at 43 mm (1.7 inches) over just 13 days, alongside a slightly reduced humidity of 75%. For more details on February weather, visit Monserrate weather in February.
In comparing the weather between September and March, September tends to be hotter and more humid. With temperatures ranging from a minimum of 25°C (77°F) to a maximum of 32°C (90°F) and an average of 28°C (82°F), it is noticeably warmer than March, where temperatures range from a minimum of 21°C (70°F) to a maximum of 31°C (87°F) with an average of 25°C (77°F). Additionally, September experiences significantly more rainfall, with 172 mm (6.8 in) over 23 days, compared to March's 72 mm (2.8 in) over just 14 days. The humidity is also slightly higher in September at 79%, while March has a humidity level of 74%. For a more detailed look at weather conditions in March, you can visit Monserrate weather in March.
September and April exhibit notable differences in weather patterns. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 32°C (90°F), with an average of 28°C (82°F). This month also sees significant rainfall, with 172 mm (6.8 in) of precipitation spread over 23 days and humidity levels averaging 79%. In contrast, April has slightly cooler temperatures, with a minimum of 22°C (71°F) and a maximum of 31°C (88°F), averaging 26°C (78°F). Additionally, April experiences much less rainfall, totaling just 55 mm (2.2 in) over 10 days, and slightly lower humidity at 75%. For a more detailed look at the weather in April, you can visit Monserrate weather in April.
When comparing the weather between September and May, there are notable differences in temperature, precipitation, and humidity levels. September tends to be slightly warmer, with an average temperature of 28°C (82°F) and maximum highs reaching 32°C (90°F). In contrast, May has a slightly cooler average of 27°C (80°F) but shares the same maximum temperature. One of the most significant differences is in precipitation: September experiences 172 mm (6.8 in) of rain over 23 days, making it much wetter than May, which has a mere 58 mm (2.3 in) over just 14 days. The humidity is also slightly higher in September at 79%, compared to May’s 75%. To learn more about the weather specifics for May, visit Monserrate weather in May.
In comparing the weather of September and June, we can observe some notable differences. Both months experience warm temperatures with September slightly edging out June, featuring minimums of 25°C (77°F) compared to June's 24°C (75°F), and average highs that reach the same maximum of 32°C (90°F). However, September is considerably wetter, receiving 172 mm (6.8 in) of rainfall over 23 days, while June has a much drier climate with only 62 mm (2.4 in) of precipitation across 15 days. Humidity levels are also quite close, with September at 79% and June at 77%. For a closer look at the specific weather patterns in June, you can check out Monserrate weather in June.
When comparing the weather in September and July, both months feature similar temperature ranges with minimums around 24-25°C (76-77°F), average highs of about 32°C (90°F), and average temperatures hovering at 28°C (82°F). However, September tends to be wetter and more humid, receiving 172 mm (6.8 in) of precipitation over 23 days, compared to July's 76 mm (3.0 in) over 17 days. Notably, September's humidity is slightly lower at 79% compared to July's 80%. For more detailed insights on July weather, you can visit this link: Monserrate weather in July.
In comparing the weather between August and September, we see some notable differences despite similar temperature ranges. Both months have a minimum temperature of 25°C (77°F) and an average of 28°C (82°F), but September experiences higher overall precipitation, measuring 172 mm (6.8 in) across 23 days compared to August’s 86 mm (3.4 in) over 18 days. Additionally, August has a slightly higher humidity level at 80% compared to September’s 79%. This increase in rainfall during September suggests a shift towards wetter conditions as the month progresses. For more details about August weather specifically, you can visit Monserrate weather in August.
September and October exhibit similar temperature ranges but show a slight decrease in both average temperature and precipitation. In September, the minimum temperature is 25°C (77°F) with an average of 28°C (82°F) and a maximum of 32°C (90°F). It also sees a higher level of rainfall, totaling 172 mm (6.8 in) over 23 days and maintaining a humidity of 79%. In contrast, October features a minimum temperature of 24°C (75°F), an average of 27°C (81°F), and a maximum of 32°C (89°F). The month experiences less rainfall, with 136 mm (5.3 in) over 22 days and slightly lower humidity at 78%. For more detailed information, check out Monserrate weather in October.
September and November offer distinct weather patterns as they transition from late summer to autumn. In September, temperatures are typically warmer, with a minimum of 25°C (77°F) and an average of 28°C (82°F), peaking at 32°C (90°F). This month also sees a higher precipitation level, with 172 mm (6.8 in) of rain over 23 days and a humidity of 79%. In contrast, November experiences slightly cooler temperatures, ranging from a minimum of 23°C (74°F) to an average of 26°C (80°F), with a maximum of 30°C (87°F). Precipitation decreases to 93 mm (3.7 in) over 17 days while humidity remains comparable at 78%. Overall, November brings milder temperatures and less rain compared to September. For more details on November weather, check out Monserrate weather in November.
In comparing the weather of September and December, we see notable differences in temperature and precipitation. September typically experiences warmer temperatures, with an average of 28°C (82°F) and maximums reaching up to 32°C (90°F). In contrast, December presents slightly cooler conditions, with an average temperature of 26°C (78°F) and maximums of 31°C (87°F).
Moreover, September is much wetter, receiving 172 mm (6.8 in) of rain over 23 days, compared to December's milder 50 mm (2.0 in) across 16 days. Humidity levels are also slightly lower in December, at 76%, compared to 79% in September. For more detailed insights, you can check Monserrate weather in December.
As September arrives in Monserrate, the weather takes on a distinctive character, marked by increased humidity and frequent rainfall. While temperatures remain warm, peaking around 32°C (90°F), the average temperature hovers comfortably at 28°C (82°F). This month sets itself apart from the drier summer months, as it experiences a notable surge in precipitation, resulting in 23 rainy days contributing to a total of 172 mm (6.8 in) of rainfall. The lush landscapes flourish during this time, yet it’s essential for visitors to stay prepared. For those planning a trip, you can gain further insights on the region's weather trends by visiting Monserrate Climate.