September Weather in Luquillo, Puerto Rico

Last updated: August 31, 2025

September in Luquillo, Puerto Rico offers a warm tropical climate, with maximum temperatures reaching a pleasant 31°C (88°F) and an average of 27°C (82°F). Visitors should prepare for a moist environment, as the area experiences significant rainfall, totaling 195 mm (7.7 in) during the month, and rainfall is recorded on 28 days. With an average humidity level of 79%, the air feels humid yet invigorating, making it an ideal time for those who appreciate lush landscapes and vibrant ecosystems. Embrace the charm of Luquillo's September weather, where the sun shines often but the rains keep the surroundings beautifully green.

September Temperature in Luquillo

In September, Luquillo, Puerto Rico, embraces the warm embrace of late summer, with temperatures showing a slight rise. The minimum temperature hovers around 24°C (76°F), while the average settles at a pleasant 27°C (82°F), making it an inviting escape for beachgoers and sun seekers alike. The peak temperatures can reach a balmy 31°C (88°F), signaling the last gasp of summer heat before the cooler months roll in. This trend of consistently warm temperatures is characteristic of Luquillo, setting a perfect backdrop for outdoor adventures, vibrant culture, and relaxation, making September an ideal time to explore this tropical paradise.

September Weather in Luquillo: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Luquillo, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Luquillo, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec767676777980818181817978
Data source: Temperature data for Luquillo generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Luquillo

September marks a notable peak in precipitation in Luquillo, Puerto Rico, with 195 mm (7.7 in) of rainfall recorded over 28 days, making it one of the wettest months of the year. This significant increase in rainfall stands out against the preceding months, where August also had high precipitation at 153 mm (6.0 in) but fewer rainy days. As the summer transitions into fall, the frequency of rainfall escalates, contributing to a lush and vibrant landscape. The trend of rising precipitation from May through September indicates a climactic shift towards the wetter season, underscoring the tropical climate's characteristic of erratic downpours that enhance the district's rich biodiversity and natural beauty.

September Precipitation Trends in Luquillo

The chart displays monthly precipitation patterns in Luquillo, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Luquillo, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec5761787910911014915319618713281
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Luquillo

September in Luquillo, Puerto Rico, presents a notable transition in humidity patterns, maintaining an average of 79%. This month typically wraps up the summer season, showing a slight dip from the peak humidity of 80% experienced in both July and August. As the year progresses from January’s relatively comfortable 76% to the humidity highs of midsummer, September marks a point where the air remains noticeably moist, yet hints at a gradual return to the lower levels seen earlier in the year. With October following closely at 78%, the trend suggests a steadying of humidity as the region heads into the cooler months. This rhythmic fluctuation is emblematic of Luquillo’s tropical climate, where the balmy air defines its charm.

September Average Humidity in Luquillo

This chart illustrates the average monthly humidity levels in Luquillo, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Luquillo is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec76%75%74%75%75%77%80%80%79%78%78%76%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Luquillo

In September, Luquillo, Puerto Rico experiences its highest UV Index of the year at a blistering 14, falling into the extreme exposure category. This stark increase marks a continuation of the relentless sun seen through the summer months, with burn times remaining critically low at just 10 minutes. As the UV Index peaks in September, it's essential for locals and visitors alike to take precautions, especially as temperatures transition into the cooler seasons. With only a slight dip in October, where the UV Index drops to 12, the region's sun intensity underscores the importance of sun safety year-round. To learn more about the UV levels throughout the year, check out the detailed information at Luquillo UV Index.

Maximum UV Index Levels in Luquillo for September

The chart shows the monthly maximum UV Index (UVI) for Luquillo in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Luquillo typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec911131313131213141298
Data source: Luquillo September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Luquillo

September in Luquillo, Puerto Rico, bathes in a delightful 318 hours of sunshine, marking it as a radiant transition into autumn. As summer wanes, the sun continues to shine brightly, although slightly less than the peak months of May and July, both of which boast over 350 hours. The overall trend showcases a generous supply of sun from January through September, with only a modest decline in the latter part of the year. This month retains substantial sunlight compared to October, which is just a whisker lower at 316 hours. Those seeking warmth and brightness will find September an inviting window to experience the vibrant beauty of Puerto Rico before the year starts to cool down.

Monthly Sunshine Duration in Luquillo: September Highlighted

The September sunshine duration represents the total number of hours Luquillo experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec258h302h348h348h357h344h354h349h318h316h302h320h
Data source: Luquillo September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Luquillo During September

In September, Luquillo, Puerto Rico, experiences a 46% chance of sunny weather—a figure that is on par with October but sits below the sunnier months of the year. This transitional period follows the more vibrant summer months, where July and August see lower probabilities of sunshine at 40% and 37%, respectively. Interestingly, September's weather offers a slight uptick compared to the preceding months, particularly April's low of 44%. As the tropical climate begins to shift towards the dryer season, visitors may find that September's mix of sun and sporadic rain can still provide delightful beach days amidst the lush greenery of this picturesque locale.

Percentage of Sunny Days in September in Luquillo

The chart illustrates the percentage of sunny days in Luquillo throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Luquillo experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec50%65%61%44%51%20%40%37%46%46%57%59%
Data source: Luquillo September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Luquillo in September

In September, Luquillo, Puerto Rico enjoys a delightful 12 hours of daylight, continuing a trend seen throughout the summer months. As the year progresses, daylight duration gradually transitions from a robust 13 hours in July and June to this balanced amount, signaling the onset of fall. The consistency of 12 hours in both August and September highlights the region's stable climate, allowing residents and visitors alike to relish the warm Caribbean days before the daylight slips back to 11 hours in October. This cyclical dance of light underscores the charm of Luquillo's tropical environment, where each season brings its own unique rhythm yet maintains a comforting familiarity.

Average Daylight Hours in Luquillo for September

The chart illustrates the variation in daylight duration in Luquillo throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 9m11h 32m12h 2m12h 33m12h 59m13h 12m13h 5m12h 42m12h 12m11h 41m11h 15m11h 2m
Data source: Luquillo daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Luquillo

In September, Luquillo, Puerto Rico experiences a shift in its breezy ambiance, with an average wind speed of 3.2 m/s (7 mph), the lowest of the year. This decline follows a summer where winds were stronger, peaking at 5.0 m/s (11 mph) in both July and August. As the tropical sun begins to wane, the gentle breezes of September invite a more tranquil atmosphere, contrasting the lively gusts of the preceding months. This pattern reveals a clear trend: wind speeds tend to dip as the summer days transition into the softer embrace of autumn, signaling a time for relaxation amidst the island's natural beauty.

Average September Wind Speed in Luquillo

The chart displays monthly wind speed patterns in Luquillo, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec4.05.04.43.74.24.75.04.43.2 m/s3.43.64.4
Data source: Luquillo September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Luquillo Compares to Other Months

Weather in Luquillo varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Luquillo, focusing on differences in temperature, rainfall, humidity, and UV levels.

In September, the weather tends to be warmer and more humid, with temperatures ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F) and an average of 27°C (82°F). The month also sees significant rainfall, accumulating 195 mm (7.7 in) over 28 days, contributing to a humidity level of 79%. In contrast, January offers a cooler and less humid experience, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 28°C (83°F), and an average of 25°C (77°F). Precipitation is noticeably lower in January, totaling 57 mm (2.3 in) across 17 days, and humidity levels are slightly reduced at 76%. For a deeper insight into January's climate, check out Luquillo weather in January.

In comparing the weather between September and February, September presents a warmer climate with average temperatures ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F). In contrast, February features cooler averages, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 27°C (81°F). Additionally, September experiences significantly more precipitation, totaling 195 mm (7.7 in) across 28 days, while February sees just 61 mm (2.4 in) over 21 days. Humidity levels are slightly higher in September at 79%, compared to 75% in February. For more details on February weather in Luquillo, check out Luquillo weather in February.

September and March exhibit notable differences in weather patterns. In September, temperatures range from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an average of 27°C (82°F). The month also sees substantial precipitation, totaling 195 mm (7.7 in) over 28 days, leading to a relatively high humidity level of 79%. In contrast, March experiences slightly cooler temperatures, with a minimum of 22°C (72°F) and a maximum of 28°C (82°F), averaging at 25°C (76°F). Precipitation is significantly lower at 78 mm (3.1 in) over 22 days, resulting in a humidity of 74%. For more detailed insights, you can check out Luquillo weather in March.

Comparing the weather of September and April reveals some interesting contrasts. September is typically warmer, with average temperatures ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F). In contrast, April sees slightly cooler averages, with temperatures fluctuating between 22°C (71°F) and 29°C (84°F). Precipitation is notably higher in September, with 195 mm (7.7 in) falling over 28 days, compared to April’s 79 mm (3.1 in) over 20 days. Additionally, the humidity levels are marginally higher in September at 79%, compared to 75% in April. For more detailed information, you can check out Luquillo weather in April.

In comparing the weather between September and May, September presents a warmer climate, with average temperatures peaking at around 27°C (82°F) and maximums reaching up to 31°C (88°F), while May's averages sit slightly lower at 26°C (79°F) with maximums of 29°C (85°F). Moreover, September experiences significantly higher precipitation, totaling 195 mm (7.7 in) across 28 days, compared to May's 109 mm (4.3 in) over 26 days. Humidity levels are also slightly higher in September at 79%, whereas May maintains a lower humidity of 75%. For a more detailed look at May's weather, you can visit Luquillo weather in May.

When comparing the weather in September and June, we find that both months feature similar temperature ranges, with September showing a slight increase in maximum temperature at 31°C (88°F) compared to June's 30°C (87°F). However, September experiences significantly higher precipitation levels, totaling 195 mm (7.7 in) over 28 days, whereas June has 110 mm (4.3 in) over 26 days. Humidity is also slightly elevated in September at 79%, compared to June's 77%. For a more detailed look at June's climate, you can check out Luquillo weather in June.

In comparing the weather of September and July, both months exhibit similarly warm temperatures, with September showing a slight increase in the maximum temperature at 31°C (88°F) compared to July's 30°C (86°F). The humidity remains high in both months, hovering around 79% in September and 80% in July, which contributes to the overall tropical climate. However, September experiences significantly more rainfall, with 195 mm (7.7 in) spread over 28 days, while July has 149 mm (5.9 in) over just 27 days, indicating that September is generally wetter. For a closer look at July's weather specifics, you can refer to Luquillo weather in July.

In comparing the weather between August and September, both months exhibit similar temperature ranges, with minimums around 24°C (76°F) and averages near 27°C (82°F). However, September slightly edges out August in terms of maximum temperature, reaching 31°C (88°F) compared to August's 30°C (87°F). Notably, September experiences more precipitation, totaling 195 mm (7.7 in) over 28 days, while August sees 153 mm (6.0 in) across 27 days. Humidity levels remain fairly consistent, with September at 79% and August at 80%. For a more detailed look at the weather specifics, you can check Luquillo weather in August.

In September, temperatures remain warm, with a minimum of 24°C (76°F), an average of 27°C (82°F), and a maximum reaching 31°C (88°F). The month experiences considerable rainfall, totaling 195 mm (7.7 in) over 28 days, paired with high humidity at 79%. In contrast, October sees a slight decline in temperature, with a minimum still at 24°C (75°F), averaging 27°C (81°F), and peaking at 30°C (87°F). The precipitation amount also decreases to 187 mm (7.4 in) across 26 days, and humidity drops slightly to 78%. For more detailed information, you can visit Luquillo weather in October.

In September, temperatures typically range from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an average of 27°C (82°F). This month also sees substantial rainfall, with a total of 195 mm (7.7 in) spread over 28 days, contributing to a high humidity level of 79%. In contrast, November brings slightly cooler temperatures, with a minimum of 23°C (74°F) and a maximum of 29°C (85°F), averaging 26°C (80°F). Rainfall decreases significantly to 131 mm (5.2 in) over 25 days, and humidity remains relatively stable at 78%. For more details about the weather in November, check out Luquillo weather in November.

In September, the weather is typically warmer with temperatures ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), and an average of 27°C (82°F). The month also sees significant rainfall, with about 195 mm (7.7 in) of precipitation spread over 28 days, resulting in a high 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 29°C (85°F). Rainfall decreases significantly to 81 mm (3.2 in) over 24 days, and humidity drops to 76%. For more details, you can check out the weather specifics at Luquillo weather in December.

Compare Luquillo's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Luquillo

As September unfolds in Luquillo, expect a distinctive blend of warmth and moisture that sets it apart from other months. With maximum temperatures reaching a pleasant 31°C (88°F) and average conditions hovering around 27°C (82°F), the tropical vibe remains inviting despite the frequent rain. This month typically witnesses heightened precipitation, with nearly the entire month featuring damp weather, making it one of the wettest times of the year. Combined with elevated humidity levels at 79%, September brings a lush ambiance that contributes to Luquillo's vibrant landscapes. For further insights into what to expect throughout the year, explore the details at Luquillo Climate.