Last updated: August 31, 2025
In September, Bayamon, Puerto Rico experiences a warm tropical climate, with maximum temperatures reaching 32°C (90°F) and an average of 27°C (81°F). The minimum temperature drops to a comfortable 23°C (74°F), making it ideal for evening strolls. However, this month also sees significant rainfall, with an impressive 200 mm (7.9 in) of precipitation spread over 27 days, contributing to a humidity level of 79%. While the frequent showers may put a damper on outdoor plans, they also rejuvenate the lush landscapes, making Bayamon a vibrant and captivating destination in early fall.
September in Bayamón, Puerto Rico, ushers in a warm and inviting climate, as it showcases a minimum temperature of 23°C (74°F) and peaks at a sizzling 32°C (90°F). The average temperature hovers around 27°C (81°F), mirroring the warm embrace of the preceding summer months. As the island transitions from the peak summer heat of August, where temperatures also reach 31°C (89°F), September offers a subtle but noticeable increase in warmth. This month stands out with its high of 32°C (90°F), making it one of the hottest times of the year. Visitors can expect plenty of sunshine, creating the perfect backdrop for outdoor activities and exploration, all while enjoying the vibrant culture of Puerto Rico.
In September, Bayamon, Puerto Rico, experiences a significant surge in precipitation, recording an impressive 200 mm (7.9 in) of rainfall over 27 days. This marks a notable peak in the yearly cycle, with September's rainfall nearly doubling that of the preceding month, August, which saw 130 mm (5.1 in). The trend indicates that as the summer wanes, the region transitions into a wetter spell, often characterized by increased storm activity. Following September, precipitation gradually tapers off in October to 183 mm (7.2 in), but remains elevated, signaling the tail-end of the wet season. This pattern reflects Bayamon's tropical climate, where late summer and early fall are marked by robust rainfall, shaping both the environment and the daily rhythms of life in this vibrant area.
September in Bayamon, Puerto Rico, typically experiences a humidity level of 79%, which reflects a slight decrease from the peak months of July and August, both at 80%. As summer wanes, the humidity begins to ease, hinting at the transition into the cooler months ahead. Overall, the data showcases a relatively stable humidity pattern throughout the year, with January through June hovering around the mid-70s to 77%, then climbing to the summer peak before tapering off again in October and November. This consistent humidity creates a warm, tropical atmosphere, characteristic of Bayamon's inviting climate.
In September, Bayamon, Puerto Rico maintains its extreme UV Index of 13, similar to the previous month, August. As the summer transitions into fall, residents and visitors must remain vigilant, as the burn time for unprotected skin is just 10 minutes. This pattern of high UV levels is consistent throughout the summer months, peaking in May, while dropping slightly in October. Overall, the trend indicates a persistent need for sun protection in Puerto Rico's tropical climate, making it essential to stay informed about daily UV readings. For more detailed information, visit Bayamon UV Index.
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September in Bayamón, Puerto Rico, offers a delightful average of 313 sunshine hours, sitting comfortably between the sunniest months of May and July. The month’s sunshine is a reminder of the vibrant summer days that precede it, marked by a gradual decrease in light as the year progresses. August enjoys a close count with 349 hours, leading into September, before the sunshine hours dip slightly in October. This trend suggests that while the days may be getting shorter, September still holds onto a substantial amount of warmth and light, making it an enjoyable time for outdoor activities and soaking in the last bits of summer. As the year transitions into autumn, Bayamón remains bathed in a golden glow, inviting locals and visitors alike to revel in its charm.
In Bayamon, Puerto Rico, September marks a slight uptick in sunny weather, with a 44% chance of sun illuminating the skies. As summer transitions into fall, this percentage reflects a gradual improvement from the notably lower chances observed in the peak summer months of June (20%) and July (38%). While September's odds are comparable to October's 44%, they still fall short of the more sun-drenched months like February (65%) and November (55%). This trend suggests that while the early weeks of September may still feel the remnants of summer, there is a promising shift towards clearer days as the month progresses.
In September, Bayamon, Puerto Rico enjoys a delightful 12 hours of daylight, maintaining the steady trend observed since May. As the summer months give way to the softer hues of autumn, daylight gradually begins its subtle decline. Interestingly, the year starts with consistent 11-hour days from January to February, before gradually stretching to a peak of 13 hours in June and July. After this zenith, daylight remains abundant before tapering off again in the fall. The seasonal rhythm of light in Bayamon, characterized by its gradual shifts, beautifully reflects the passage of time on this vibrant island.
As September unfolds in Bayamon, Puerto Rico, the gentle caress of the wind takes a noticeable dip, averaging a mere 2.4 m/s (5 mph). This marks a decline from the breezier months of July and August, which both enjoyed winds at 4.0 m/s (9 mph) and 3.5 m/s (8 mph) respectively. The arrival of early autumn brings a tranquility to the air, contrasting the more dynamic winds that typically characterize the summer months. Following September’s lull, the wind speeds show only a slight increase in October to 2.6 m/s (6 mph), illustrating a continuing trend of gentle breezes as the year transitions further into the cooler season. This overall softening of wind patterns serves to create a serene ambiance, perfect for enjoying Bayamon’s picturesque landscapes.
Weather in Bayamon varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Bayamon, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January showcase distinctly different weather patterns. In September, temperatures typically range from a minimum of 23°C (74°F) to a maximum of 32°C (90°F), with an average temperature of 27°C (81°F). This month is also characterized by high humidity at 79% and significant rainfall, accumulating about 200 mm (7.9 in) over 27 days. In contrast, January brings cooler temperatures, with a minimum of 19°C (66°F), an average of 24°C (76°F), and a maximum of 29°C (84°F). Precipitation is notably lower at 48 mm (1.9 in) across 16 days, and humidity decreases slightly to 76%. For more details on January weather, you can check Bayamon weather in January.
In comparing the weather between September and February, September is generally warmer and more humid. The average temperature in September reaches around 27°C (81°F) with maximums hitting 32°C (90°F), whereas February sees a cooler average of 24°C (75°F) and a maximum of 28°C (83°F). Additionally, September experiences significantly more rainfall, totaling 200 mm (7.9 in) over 27 days, compared to February's milder 53 mm (2.1 in) over 18 days. The humidity in September is higher at 79%, while February maintains a comfortable 75%. For more specifics on February weather, you can visit Bayamon weather in February.
In comparing the weather between September and March, September typically showcases warmer temperatures with a minimum of 23°C (74°F) and an average of 27°C (81°F), peaking at a maximum of 32°C (90°F). The month also experiences significant rainfall, totaling 200 mm (7.9 in) across 27 days, alongside a high humidity level of 79%. In contrast, March presents a slightly cooler climate, with minimum temperatures around 20°C (69°F) and an average of 24°C (76°F), reaching a maximum of 29°C (85°F). Precipitation is much less in March, amounting to 80 mm (3.2 in) over 21 days, and humidity is relatively lower at 74%. For more detailed information, you can check out Bayamon weather in March.
In September, the weather is typically warmer and more humid compared to April, with temperatures ranging from a minimum of 23°C (74°F) to a maximum of 32°C (90°F) and an average of 27°C (81°F). This month also sees significant rainfall, with 200 mm (7.9 in) of precipitation spread over 27 days, resulting in a humidity level of 79%. In contrast, April has slightly cooler temperatures, with a minimum of 21°C (70°F), an average of 25°C (77°F), and a maximum of 30°C (86°F). The precipitation in April is much lower, totaling 77 mm (3.0 in) over 20 days, and the humidity is slightly lower at 75%. For more details, you can check Bayamon weather in April.
September and May weather show some similarities and differences that characterize each month. In September, temperatures range from a minimum of 23°C (74°F) to a maximum of 32°C (90°F), with an average of 27°C (81°F). This month also experiences higher precipitation, totaling 200 mm (7.9 in) over 27 days, along with a humidity level of 79%. In contrast, May has slightly cooler temperatures, with a minimum of 22°C (72°F), an average of 26°C (79°F), and a maximum of 31°C (87°F). Additionally, May sees significantly less rainfall, with 98 mm (3.9 in) over 24 days and lower humidity at 75%. For more detailed information on weather patterns, you can check Bayamon weather in May.
September and June share similar average temperatures, with both months having a minimum of 23°C (74°F) and an average around 27°C (81°F). However, September tends to be slightly warmer, peaking at a maximum of 32°C (90°F) compared to June's high of 31°C (88°F). One notable difference is the weather patterns, as September experiences significantly more rainfall, totaling 200 mm (7.9 in) over 27 days, whereas June sees much less precipitation at 99 mm (3.9 in) across 23 days. Additionally, humidity levels are marginally higher in September at 79%, compared to June’s 77%. For a detailed look at weather specifics, you can check Bayamon weather in June.
In comparing the weather between September and July, both months exhibit warm temperatures, with September slightly warmer, featuring a maximum of 32°C (90°F) compared to July's max of 31°C (88°F). The minimum temperatures remain the same at 23°C (74°F) for both months, and the average temperature is also consistent at 27°C (81°F). However, September experiences significantly higher precipitation, measuring 200 mm (7.9 in) across 27 days, while July has only 124 mm (4.9 in) over 24 days. Humidity levels are quite similar, with September at 79% and July at 80%. For more details, you can check the full breakdown of Bayamon weather in July.
In comparing the weather of September to that of August, we observe that both months have similar temperature averages, with a minimum of 23°C (74°F) and an average of 27°C (81°F). However, September experiences slightly higher maximum temperatures, reaching 32°C (90°F), compared to August's maximum of 31°C (89°F). Precipitation is notably greater in September, with 200 mm (7.9 in) recorded over 27 days, while August sees 130 mm (5.1 in) over 25 days. Humidity levels remain fairly consistent, with September at 79% and August at 80%. For more specifics about August's weather, you can visit Bayamon weather in August.
In September, the weather tends to be slightly warmer, with temperatures reaching a maximum of 32°C (90°F) and an average of 27°C (81°F). The month is characterized by high humidity at 79% and significant rainfall, totaling 200 mm (7.9 in) over 27 days. In contrast, October sees a marginal decline in maximum temperatures to 31°C (88°F) while maintaining the same minimum and average temperatures as September. Precipitation in October is also lower, with totals around 183 mm (7.2 in), but humidity remains similar at 78%. For more detailed insights into the weather in October, you can check Bayamon weather in October.
In comparing the weather of September and November, we see some notable differences. September tends to be warmer, with average temperatures reaching 27°C (81°F) and maximums peaking at 32°C (90°F). In contrast, November features slightly cooler conditions, with an average temperature of 26°C (79°F) and a maximum of 30°C (86°F). Additionally, September experiences significantly more rainfall, totaling 200 mm (7.9 in) over 27 days, compared to November's 120 mm (4.7 in) across 23 days. Humidity levels remain similar in both months, with September at 79% and November at 78%. For a detailed look at November weather, visit Bayamon weather in November.
In September, the weather is generally warmer, with minimum temperatures around 23°C (74°F) and maximums reaching up to 32°C (90°F), creating a humid and vibrant atmosphere. The month sees considerable rainfall, averaging 200 mm (7.9 in) across 27 days, contributing to the high humidity levels of 79%. In contrast, December brings slightly cooler temperatures, with minimums of 21°C (71°F) and maximums peaking at 30°C (86°F). Precipitation in December decreases significantly to 66 mm (2.6 in) over 22 days, with a humidity level of 76%. This shift makes December a more comfortable month for outdoor activities. For more detailed insights, you can check Bayamon weather in December.
As September unfolds in Bayamon, it brings a distinct shift in weather patterns compared to other months. The temperatures remain warm, but the increased humidity and frequent rainfall, with nearly 27 days of precipitation totaling about 200 mm, create a more tropical atmosphere. This notable uptick in moisture can make the air feel heavier and the surroundings lush. Despite the rain, the average temperature hovers pleasantly, allowing for a mix of both sun and the refreshing embrace of summer showers. For those looking to understand the year-round climate nuances, explore more about the weather dynamics in this vibrant region at Bayamon Climate.