Last updated: August 31, 2025
In September, Loiza, Puerto Rico experiences a warm tropical climate characterized by an average temperature of 28°C (82°F), with maximum highs reaching 32°C (90°F) and lows around 24°C (76°F). This month is notably wet, with total precipitation averaging 173 mm (6.8 in) over approximately 23 days. The humidity remains elevated at 79%, contributing to a sultry atmosphere. Visitors can expect a blend of sunshine and rain, making it essential to be prepared for sudden downpours amidst the Caribbean warmth.
In Loiza, Puerto Rico, September brings warm and consistent temperatures that reflect the lingering embrace of summer. With minimums hovering around 24°C (76°F) and average highs reaching a balmy 32°C (90°F), the weather is perfect for enjoying the island's stunning beaches and vibrant culture. The season transitions smoothly into fall, where temperatures remain stable, with averages of 28°C (82°F), offering both comfort and warmth. This month shares a pattern with August, marked by high humidity and tropical breezes, creating an inviting atmosphere for outdoor adventures. Travelers can expect a lively yet relaxing environment as they soak in the last rays of summer before the cooler months set in.
September marks a significant turning point in Loiza, Puerto Rico's precipitation patterns, as the island experiences its highest rainfall of the year, with a staggering 173 mm (6.8 in). This surge is coupled with 23 days of rain, underscoring September's reputation as a particularly wet month. Compared to the preceding months, where rainfall gradually increased from January's modest 38 mm (1.5 in), September’s deluge is almost double that of the previous month, August, which saw 99 mm (3.9 in) over 18 days. As the wettest month, September plays a crucial role in replenishing the region's water supply and underscores the dynamic nature of Puerto Rico's tropical climate, where summer transitions into fall with an emphatic increase in precipitation.
In September, the humidity in Loiza, Puerto Rico, hovers around 79%, marking a slight dip from the peak levels seen in the summer months of July and August, which both recorded 80%. This seasonal transition reflects a gradual decrease as the island shifts from the humid summer into the cooler fall months. Notably, the levels remain consistently elevated throughout the year, alternating between the mid-70s and low-80s, with September maintaining humidity higher than the annual average. This persistent moisture is characteristic of the tropical climate, contributing to Loiza's lush landscapes and vibrant ecosystems. As autumn approaches, residents and visitors alike can expect slightly more comfortable conditions, while still enjoying the tropical beauty that Puerto Rico has to offer.
In September, Loiza, Puerto Rico continues to experience an extreme UV Index of 13, necessitating a brief exposure limit of just 10 minutes to avoid sunburn. As the summer months transition into fall, the UV levels remain consistently high, mirroring the trend observed in May through August. This persistent intensity indicates that outdoor enthusiasts and beachgoers must remain vigilant about sun protection, as the UV Index rarely dips below 12 during this part of the year. In fact, the overall trend for the late summer and early fall months reveals that high UV levels dominate, emphasizing the importance of sunscreen and protective measures to safeguard against the sun's harsh rays. Stay informed and prepare by checking the detailed Loiza UV Index for the best safety practices!
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In Loiza, Puerto Rico, September shines brightly with 313 hours of sunshine, nestled between the vibrant summer months of July and August, which boast 353 and 349 hours respectively. This trend highlights a gradual decrease in daylight as autumn approaches, yet September still offers a warm embrace of summer’s lingering rays. Following a peak in sunshine hours during the bustling late spring and early summer months, the consistent sunlight in September provides an ideal backdrop for locals and travelers alike to enjoy the island's rich culture and stunning landscapes. As the seasons transition, Loiza remains a captivating destination, balancing sunny days with the anticipation of the autumn months ahead.
In Loiza, Puerto Rico, the prospects for sunny weather in September show a modest likelihood, with a 48% chance of sunshine. This month sits just above the slightly overcast summer months but trails behind the more favorable conditions of early spring and late fall. Notably, February peaks with a 70% chance, making it one of the sunniest times of the year, while the sweltering June and July months reflect a significant drop in sunny days at 24% and 43%, respectively. As September approaches, locals and visitors alike can expect a blend of both sunshine and occasional rain, with weather patterns gradually stabilizing toward more favorable conditions as they head into October.
In Loiza, Puerto Rico, September offers a delightful continuation of the summer's vibrant daylight, boasting around 12 hours of sunlight each day. This marks a subtle transition from the longer days of June and July, which peak at 13 hours, gradually shifting back toward the shorter daylight hours experienced in the winter months. As summer fades, the consistent daylight duration in September signals a time of balance, providing ample opportunity to enjoy the lush landscapes and warm temperatures. With daylight duration steadily diminishing in October, this month's moderate light serves as a gentle reminder of the changing seasons while still allowing for outdoor adventures under the sun.
As summer transitions to fall, September in Loiza, Puerto Rico, brings a gentle shift in the atmosphere, marked by a notable decrease in average wind speed to 3.2 m/s (7 mph). This dip stands in contrast to the more robust winds of the preceding months, which frequently reached 5.3 m/s (12 mph) in July and hovered around 4.6 m/s (10 mph) in August. The overall trend from January to September showcases a gradual rise in wind speeds during the early summer months, followed by a calming in September, setting the stage for the milder breezes of October and November. This serene wind pattern, reminiscent of a lull before the more turbulent months ahead, offers an inviting atmosphere for those looking to soak in the tranquil vibe of the island as it prepares for the autumn transition.
Weather in Loiza varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Loiza, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather tends to be hotter and more humid, with average temperatures reaching 28°C (82°F) and maximums peaking at 32°C (90°F). This month also sees substantial rainfall, totaling 173 mm (6.8 in) over 23 days, contributing to a humidity level of 79%. In contrast, January offers cooler and drier conditions, with average temperatures at 25°C (77°F) and maximums of 29°C (85°F). Precipitation is significantly lower in January, with only 38 mm (1.5 in) recorded over 12 days, and humidity slightly decreased at 76%. For more detailed insights, you can check out Loiza weather in January.
In comparing the weather of September and February, September tends to be warmer and more humid. With average temperatures around 28°C (82°F) and maximums reaching up to 32°C (90°F), it creates a distinctly tropical atmosphere. Additionally, September experiences significantly higher rainfall, with total precipitation at 173 mm (6.8 in) over 23 days, leading to a humidity level of 79%. In contrast, February features milder temperatures, with averages around 25°C (77°F) and maximums peaking at 29°C (85°F). The month sees considerably less rainfall, totaling only 43 mm (1.7 in) across 12 days, and a slightly lower humidity of 75%. For more detailed information on February weather, you can check Loiza weather in February.
When comparing the weather in September and March, September tends to be warmer and more humid. In September, temperatures range from a minimum of 24°C (76°F) to a maximum of 32°C (90°F), with an average temperature of 28°C (82°F). Additionally, it experiences significant rainfall, with 173 mm (6.8 in) over approximately 23 days, resulting in a high humidity level of 79%.
In contrast, March is slightly cooler, with temperatures ranging from 21°C (71°F) to 30°C (86°F), averaging 25°C (77°F). Rainfall during March is considerably less, at 67 mm (2.6 in) spread over about 14 days, and humidity levels are also lower at 74%. For more details on March weather, you can visit Loiza weather in March.
In September, the weather is typically warmer and more humid, with average temperatures ranging from a minimum of 24°C (76°F) to a maximum of 32°C (90°F). This month also experiences substantial rainfall, averaging 173 mm (6.8 in) over 23 days, resulting in a humidity level of 79%. In contrast, April features slightly cooler temperatures, with a minimum of 22°C (71°F) and a maximum of 31°C (88°F), along with significantly less precipitation of 56 mm (2.2 in) over just 10 days and a humidity level of 75%. For more detailed information, you can check Loiza weather in April.
In September, the weather remains warm with minimum temperatures around 24°C (76°F) and average highs reaching up to 32°C (90°F), mirroring the peaks seen in May. However, September is notably wetter, with a significant 173 mm (6.8 in) of precipitation over 23 days, compared to May’s much drier conditions, which experience only 64 mm (2.5 in) of rainfall across 13 days. Humidity levels also differ slightly, with September averaging 79%, while May holds a more comfortable average of 75%. For more specific details on the weather in May, you can visit Loiza weather in May.
In comparing the weather of September and June, both months share similar temperature ranges, with minimums around 24°C (75-76°F) and maximums reaching 32°C (90°F). However, September tends to be slightly warmer on average, at 28°C (82°F) compared to June's average of 27°C (81°F). The most notable difference lies in precipitation; September experiences significantly higher rainfall, with 173 mm (6.8 in) over 23 days, while June has only 68 mm (2.7 in) over 15 days. Humidity levels are also similar, but September is marginally more humid at 79%, compared to June's 77%. For a detailed look at June weather, visit Loiza weather in June.
When comparing the weather in September and July, we see that both months share similar temperature ranges, with minimums of 24°C (76°F), average highs of 28°C (82°F), and maximums reaching 32°C (90°F). However, September is notably wetter, receiving 173 mm (6.8 in) of precipitation over 23 days, in contrast to July's 87 mm (3.4 in) over 18 days. Humidity levels are slightly lower in July at 80%, compared to September's 79%. For more details, you can check Loiza weather in July.
In September, the weather remains quite consistent with August, as both months feature similar temperature ranges, with minimums of 24°C (76°F), averages of 28°C (82°F), and maximums of 32°C (90°F). However, September experiences significantly more rainfall, accumulating 173 mm (6.8 in) over 23 days, compared to August's 99 mm (3.9 in) across 18 days. Additionally, while humidity levels are slightly lower in September at 79%, they remain close to the 80% recorded in August. For a more detailed look at August weather patterns in Loiza, you can check Loiza weather in August.
September and October display similar temperatures, with both months maintaining a minimum of 24°C (76°F) and a maximum reaching 32°C (90°F). However, October's average temperature is slightly lower at 27°C (81°F) compared to September's 28°C (82°F). Precipitation also decreases in October, with a total of 145 mm (5.7 in) over 22 days, compared to September's 173 mm (6.8 in) over 23 days. Additionally, October experiences a marginally lower humidity level at 78%, compared to September's 79%. For more details, check out Loiza weather in October.
In September, the weather is typically warmer, with average temperatures reaching 28°C (82°F), and highs peaking at 32°C (90°F). This month experiences significant rainfall, with 173 mm (6.8 in) falling over 23 days, contributing to a humid atmosphere with 79% humidity. In contrast, November sees slightly cooler temperatures, averaging 26°C (80°F) and reaching a maximum of 31°C (87°F). The precipitation drops to 106 mm (4.2 in), occurring over 16 days, and the humidity remains fairly consistent at 78%. For more detailed insights into November's weather, you can check out Loiza weather in November.
September and December present distinct weather patterns. In September, temperatures are generally warmer, with a minimum of 24°C (76°F), an average of 28°C (82°F), and a maximum of 32°C (90°F). However, it is also the rainiest month, receiving 173 mm (6.8 in) of precipitation over 23 days, contributing to a humidity level of 79%. In contrast, December offers slightly cooler temperatures, with a minimum of 23°C (73°F), an average of 26°C (78°F), and a maximum of 31°C (87°F). Additionally, this month experiences significantly lower precipitation, totaling 51 mm (2.0 in) across 16 days, and a slight drop in humidity to 76%. For more details about the weather in December, you can check Loiza weather in December.
As September rolls in, Loiza experiences a distinct shift in weather patterns compared to other months. With temperatures averaging around 28°C (82°F), the warmth is accompanied by high humidity levels at 79%, creating a tropical atmosphere. However, this month is notably marked by frequent rainfall, accumulating approximately 173 mm (6.8 in) over 23 days, making it one of the wetter times of the year. This increased precipitation not only enriches the lush landscapes but also creates a vibrant, refreshing ambience that sets September apart from its drier counterparts. For more insights into the region's climate, visit Loiza Climate.