September Weather in Fajardo, Puerto Rico

Last updated: August 31, 2025

In September, Fajardo, Puerto Rico, experiences a tropical climate characterized by warm temperatures and high humidity. With a maximum temperature reaching up to 31°C (88°F) and an average of 27°C (82°F), the weather remains consistently warm, while the minimum temperature rarely dips below 24°C (76°F). This month also sees significant precipitation, totaling 195 mm (7.7 in) over 28 days, making it one of the wetter periods of the year. Combined with a humidity level averaging 79%, September in Fajardo offers a lush, vibrant landscape, highlighting the beauty and dynamism of Puerto Rican weather.

September Temperature in Fajardo

In September, Fajardo, Puerto Rico, basks in warm tropical weather, marking the transition from summer to fall. The temperatures during this month typically range from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an inviting average of 27°C (82°F). This trend showcases a slight increase in warmth compared to the preceding months, hinting at the lingering summer heat. As September also signals the heart of the hurricane season, visitors are advised to stay informed while enjoying the sun-soaked days and vibrant evenings typical of this beautiful coastal town. The comfort of the warm sea and colorful sunsets make it a captivating time to experience Fajardo.

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

The chart illustrates September temperature patterns in Fajardo, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Fajardo, 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 Fajardo generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Fajardo

September marks a peak in precipitation for Fajardo, Puerto Rico, with an impressive 195 mm (7.7 in) of rain falling over 28 days. This significant increase in rainfall, compared to previous months, reflects a clear trend as the region transitions into the wetter season. Following the summer months of July and August, which also feature high rainfall, September showcases the culmination of storm patterns, adding to the lush, tropical environment. As we move from the summer's peak to milder conditions in October, the lingering September showers often create vivid landscapes, emphasizing the beauty of Puerto Rico's natural scenery forged by its diverse rainfall patterns.

September Precipitation Trends in Fajardo

The chart displays monthly precipitation patterns in Fajardo, 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 Fajardo, 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.
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September Humidity in Fajardo

In Fajardo, Puerto Rico, September offers a relative reprieve in humidity, with levels averaging around 79%. This slight decline follows the peak summer months of July and August, which both register a high of 80%. The trend shows that as summer wanes, humidity levels modestly drop but remain consistently high compared to the cooler months, where humidity averages hover between 74% and 76%. As the year progresses into October, humidity remains comparable at 78%, suggesting that while fall brings slight relief, the tropical climate retains its characteristic moistness throughout much of the year. The gradual ebb and flow of humidity in Fajardo not only shapes the local environment but also adds to the region's lush, vibrant scenery.

September Average Humidity in Fajardo

This chart illustrates the average monthly humidity levels in Fajardo, 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 Fajardo 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 Fajardo

In Fajardo, Puerto Rico, September marks a peak in sun intensity, boasting a UV Index of 14, classified as extreme with a dangerously short burn time of just 10 minutes. This trend of elevated UV levels, prevalent throughout the summer months, highlights the need for sun protection, especially as the year moves from the high of summer and into the early fall. Notably, the UV Index remains consistently high from February through September, with values hitting extremes in the spring and summer. As temperatures cool slightly in October, the UV Index does drop to 12, yet the caution advised in September remains relevant year-round. For those enjoying Fajardo's beautiful outdoors, staying informed about the UV Index is essential—check out the detailed forecast at Fajardo UV Index.

Maximum UV Index Levels in Fajardo for September

The chart shows the monthly maximum UV Index (UVI) for Fajardo 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 Fajardo typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec911131313131213141298
Data source: Fajardo 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 Fajardo

In Fajardo, Puerto Rico, September shines brightly with an impressive 318 hours of sunshine, making it a delightful time to soak up the sun. This month stands out as a continuation of the warm, sun-soaked summer months, following July's peak of 354 hours. The sunshine slowly begins to taper off into the fall, as October brings slightly less light with 316 hours. Overall, this consistent abundance of sunlight from January through September showcases Fajardo's vibrant tropical climate, where sunshine remains a central feature year-round, making it a perfect escape for sun-seekers and outdoor enthusiasts alike.

Monthly Sunshine Duration in Fajardo: September Highlighted

The September sunshine duration represents the total number of hours Fajardo 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: Fajardo September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Fajardo During September

In Fajardo, Puerto Rico, the likelihood of sunny weather in September hovers around 46%, reflecting a trend of variability throughout the year. While January and February boast higher chances of sun at 50% and 65%, respectively, the summer months take a dip, with June reaching as low as 20%. Interestingly, September's sunshine probability is akin to October's, both sitting at 46%, suggesting that the transition to autumn doesn't drastically change the weather patterns. As we move towards the end of the year, the chance of sunny days begins to rise again, with November and December offering increased sunshine, peaking at 59%. Overall, September stands out as a month of fluctuating but promising sunny possibilities.

Percentage of Sunny Days in September in Fajardo

The chart illustrates the percentage of sunny days in Fajardo 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 Fajardo experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec50%65%61%44%51%20%40%37%46%46%57%59%
Data source: Fajardo September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Fajardo in September

In Fajardo, Puerto Rico, the daylight duration exhibits a captivating rhythm throughout the year, with September enjoying a generous 12 hours of sunlight. This month marks a transition point where daylight begins to taper off after the summer months, paralleling the patterns observed from March to August, where longer days prevail. Interestingly, the daylight duration remains consistent in September compared to August, hinting at the lingering warmth of late summer. As the year progresses towards October, the sunlight gently recedes to 11 hours, signaling the onset of shorter days. This gradual shift underscores the tropical charm of Fajardo, where daylight creates a vibrant backdrop for both relaxed beach days and captivating sunsets.

Average Daylight Hours in Fajardo for September

The chart illustrates the variation in daylight duration in Fajardo 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: Fajardo daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Fajardo

In September, Fajardo, Puerto Rico, experiences its gentlest winds of the year, with an average speed of only 3.2 m/s (7 mph). This month marks a notable dip from the breezy summer months, where winds ranged from 4.4 m/s to 5.0 m/s from June to August. As the tropical heat begins to ease, the calmer breezes of September create a serene backdrop, perfect for leisurely strolls along the coast or enjoying the tranquil waters. Interestingly, this trend of decreasing wind speed continues into the fall, with October and November showing only slight increases. Overall, September's mellow winds invite relaxation and reflection, a delightful contrast to the preceding summer's playful gusts.

Average September Wind Speed in Fajardo

The chart displays monthly wind speed patterns in Fajardo, 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: Fajardo September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Fajardo Compares to Other Months

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

In September, temperatures in Fajardo are notably warmer, ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an average temperature of 27°C (82°F). The month is also characterized by higher precipitation, totaling 195 mm (7.7 in) over 28 days, and a humidity level of 79%. In contrast, January experiences milder weather, 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). The rainfall in January is significantly reduced to 57 mm (2.3 in) over 17 days, and humidity dips slightly to 76%. For more details on the January weather, see Fajardo weather in January.

September and February exhibit notable differences in weather patterns. In September, temperatures are warmer with a minimum of 24°C (76°F) and an average high reaching 31°C (88°F), while February boasts cooler temperatures with a minimum of 21°C (70°F) and maximums around 27°C (81°F). Additionally, September experiences higher precipitation, totaling 195 mm (7.7 in) over 28 days, compared to February's 61 mm (2.4 in) across 21 days. Humidity levels are slightly elevated in September at 79%, while February's humidity is a bit lower at 75%. For more detailed information, check out Fajardo weather in February.

September and March exhibit notable differences in weather patterns. September tends to be warmer, with temperatures ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F) and an average temperature of 27°C (82°F). In contrast, March offers slightly cooler conditions, with temperatures varying from a minimum of 22°C (72°F) to a maximum of 28°C (82°F) and an average of 25°C (76°F). Additionally, September experiences significantly higher precipitation, totaling 195 mm (7.7 in) over 28 days, compared to March’s 78 mm (3.1 in) over 22 days. Humidity levels are also slightly higher in September at 79%, while March has a humidity level of 74%. For more detailed information, you can visit Fajardo weather in March.

In comparing the weather of September and April, September tends to be warmer with average temperatures ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), while April has slightly cooler temperatures averaging between 22°C (71°F) and 29°C (84°F). Additionally, September experiences significantly higher precipitation with 195 mm (7.7 in) over 28 days, compared to April's 79 mm (3.1 in) over 20 days. Humidity levels are relatively similar, with September at 79% and April slightly lower at 75%. For more detailed information about April weather, you can check out Fajardo weather in April.

When comparing the weather in September and May, September tends to be warmer and wetter. September boasts temperatures ranging from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an average of 27°C (82°F). In contrast, May has slightly cooler temperatures, with a minimum of 23°C (73°F), an average of 26°C (79°F), and a maximum of 29°C (85°F). Additionally, September experiences significantly higher precipitation, totaling 195 mm (7.7 in) over 28 days, compared to May, which sees 109 mm (4.3 in) over 26 days. Humidity levels are also slightly higher in September at 79%, while May's humidity averages around 75%. For more detailed information about May weather, check out Fajardo weather in May.

The weather in September and June shows some similarities, as both months have a minimum temperature of around 24°C (75°F) and an average temperature close to 27°C (80°F). However, September tends to be slightly warmer with a maximum temperature of 31°C (88°F), compared to June's 30°C (87°F). Precipitation levels differ notably, with September receiving 195 mm (7.7 in) over 28 days, while June sees just 110 mm (4.3 in) across 26 days, making September significantly wetter. Additionally, September's humidity is slightly higher at 79%, compared to June's 77%. For more details, you can check Fajardo weather in June.

In comparing the weather of September to July, we see similar warm temperatures, with both months experiencing a minimum of around 24°C (75°F), average temperatures close to 27°C (81°F), and maximums reaching 30-31°C (86-88°F). However, September is notably wetter, with a total precipitation of 195 mm (7.7 in) across 28 days, compared to July's 149 mm (5.9 in) over 27 days. Additionally, humidity remains high in both months, averaging 79% in September and 80% in July. For more detailed insights, check out this resource: Fajardo weather in July.

In comparing the weather between August and September, both months display similar temperature ranges, with minimum temperatures consistently around 24°C (76°F) and average temperatures hovering at 27°C (82°F). However, September experiences slightly higher maximum temperatures, reaching up to 31°C (88°F), compared to August's 30°C (87°F). Precipitation also increases notably in September, totaling 195 mm (7.7 in) over 28 days, compared to August's 153 mm (6.0 in) over 27 days. Humidity remains relatively stable, with September at 79% and August slightly higher at 80%. For a closer look at August's weather specifics, you can check Fajardo weather in August.

September and October share similar weather patterns, but October tends to be slightly milder. Both months have a minimum temperature of around 24°C (75°F), with October averaging a degree lower at 27°C (81°F) compared to September's 27°C (82°F). The maximum temperatures in October reach up to 30°C (87°F), just a degree cooler than September's 31°C (88°F). While both months experience considerable rainfall, September sees 195 mm (7.7 in) over 28 days, whereas October has slightly less precipitation at 187 mm (7.4 in) over 26 days. Humidity remains quite high in both months, with September at 79% and October at 78%. For a more detailed look at October weather, you can check Fajardo weather in October.

In comparing the weather conditions of September and November, September exhibits slightly warmer temperatures, with an average of 27°C (82°F), while November sees a decrease to an average of 26°C (80°F). Although both months maintain high humidity levels, September has a marginally higher humidity rate of 79%, compared to November's 78%. Rainfall is notably more prevalent in September, with 195 mm (7.7 in) of precipitation over 28 days, while November experiences less rainfall at 131 mm (5.2 in) over 25 days. For more specific details about November weather, you can check Fajardo weather in November.

In comparing the weather between September and December, September tends to be warmer, with average temperatures reaching 27°C (82°F) and maximums of 31°C (88°F). In contrast, December features slightly cooler temperatures, with an average of 26°C (78°F) and maximums of 29°C (85°F). Additionally, September experiences significantly higher precipitation, totaling 195 mm (7.7 in) over 28 days, compared to December’s much drier 81 mm (3.2 in) over 24 days. Humidity levels are also slightly higher in September at 79%, while December's humidity remains at 76%. For more specific weather details, you can check Fajardo weather in December.

Compare Fajardo's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Fajardo

As September unfolds in Fajardo, the weather takes on a distinct character, marked by high humidity and frequent rainfall that sets it apart from the drier summer months. While temperatures remain pleasantly warm, hovering around 27°C (82°F) on average, the near-daily precipitation—totaling an impressive 195 mm (7.7 in)—creates a lush, vibrant landscape. With rain gracing nearly every day of the month, September offers a unique blend of tropical beauty that invites visitors to experience the island's natural wonders. For more insights into what to expect throughout the year, visit Fajardo Climate.