September Weather in Cabo Frio, Brazil

Last updated: August 21, 2025

September in Cabo Frio, Brazil, offers a delightful transition into spring, with average temperatures hovering around 22°C (72°F). Visitors can expect warm days with maximum highs of 26°C (78°F) and refreshing evenings cooling down to 19°C (67°F). Although the month sees about 41 mm (1.6 in) of precipitation over a span of 5 days, the humidity level at 75% adds to the lively coastal atmosphere. This combination of pleasant weather and occasional showers creates a perfect backdrop for exploration and relaxation in this stunning beach destination.

September Temperature in Cabo Frio

In September, Cabo Frio, Brazil experiences a refreshing transition as the temperature maintains a pleasant range. With minimums around 19°C (67°F) and maximums peaking at 26°C (78°F), the average settles comfortably at 22°C (72°F). This period marks a return to warmer weather after the cooler winter months, reminiscent of the balmy conditions felt earlier in the year. The gradual rise in temperatures sets the stage for outdoor adventures, making September an ideal time to explore Cabo Frio’s stunning beaches and vibrant local culture. As the spring season blooms, the weather invites both relaxation and activity, providing a perfect backdrop for visitors looking to soak in the sun.

September Weather in Cabo Frio: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Cabo Frio, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Cabo Frio, 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).
JanFebMarAprMayJunJulAugSepOctNovDec777777767372717071727375
Data source: Temperature data for Cabo Frio 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 Cabo Frio

In September, Cabo Frio experiences a gentle transition in its precipitation patterns, with an average of 41 mm (or 1.6 inches) of rainfall spread across just 5 days. This modest amount marks a slight decrease compared to the preceding months, contributing to a more stable and pleasant climate as the region edges closer to the more humid spring season. Following the typically wet months of March and November, September's rainfall hints at a breather before the subsequent increase in precipitation later in the year, offering residents and visitors a delightful mix of sunny spells and refreshing showers. Overall, September heralds a calm yet vibrant phase in Cabo Frio's weather, perfect for outdoor activities and enjoying the coastal beauty.

September Precipitation Trends in Cabo Frio

The chart displays monthly precipitation patterns in Cabo Frio, 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 Cabo Frio, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec387712651734128504167109101
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Cabo Frio

In Cabo Frio, Brazil, September marks a continuation of the subtle decline in humidity that characterizes the late winter months. With humidity stabilizing at 75%, the atmosphere becomes increasingly comfortable as the city transitions towards the warmer spring season. This figure represents a notable decrease from the peak humidity levels experienced earlier in the year, with values reaching as high as 86% in February. The trend showcases a gradual shift towards drier conditions, setting the stage for pleasant days ahead, as Cabo Frio prepares to usher in more temperate weather. Overall, September's humidity is a relief for visitors and residents alike, offering a refreshing respite from the higher levels of the preceding months.

September Average Humidity in Cabo Frio

This chart illustrates the average monthly humidity levels in Cabo Frio, 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 Cabo Frio is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec85%86%84%82%80%78%77%75%76%74%79%81%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Cabo Frio

As September rolls into Cabo Frio, Brazil, the UV Index remains in the extreme category at 11, with a burn time of just 10 minutes—a reminder of the intense sun this month. This level of UV exposure reflects a trend observed throughout the year, where the first half consistently showcases extremely high indexes, peaking at a striking 16 in January. As the seasons change, September signals a return to the higher extremes, similar to April's mild retreat from peak intensity and leading us toward the higher values of October and November. Whether basking on the beach or exploring the vibrant city, it's crucial to stay protected under the sun. For a detailed view of the UV trends year-round, visit Cabo Frio UV Index.

Maximum UV Index Levels in Cabo Frio for September

The chart shows the monthly maximum UV Index (UVI) for Cabo Frio 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 Cabo Frio typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec16141311867911131415
Data source: Cabo Frio 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 Cabo Frio

September in Cabo Frio, Brazil, welcomes 305 hours of sunshine, marking a continuation of the delightful weather experienced throughout the year. As the summer season transitions into spring, sunlight remains abundant, contributing to the area's vibrant outdoor culture. Interestingly, September's sunshine hours align with those of April, showcasing a steady pattern that keeps visitors and locals alike basking in the warm embrace of sunlight. This month sits comfortably amid a consistent range of sunny days, right before the peak of sunshine in December, which records a spectacular 336 hours. Whether you're savoring the stunning beaches or exploring local attractions, September's radiant weather sets the perfect stage for unforgettable experiences in this coastal paradise.

Monthly Sunshine Duration in Cabo Frio: September Highlighted

The September sunshine duration represents the total number of hours Cabo Frio 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.
JanFebMarAprMayJunJulAugSepOctNovDec290h285h324h305h289h285h295h291h305h299h307h336h
Data source: Cabo Frio September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Cabo Frio During September

As summer transitions into fall, Cabo Frio experiences a notable shift in sunshine probabilities. In September, the likelihood of sunny weather rests at 48%, marking a slight dip compared to the sunnier months of July and August, which enjoy robust chances of 64% and 60%, respectively. This trend suggests that while September may not be the sunniest month, it still offers plenty of bright days, aligning it more closely with the sun-kissed spring months rather than the cloudier ones that follow in October. Overall, visitors in September can anticipate a mix of warm sunshine and occasional cloud cover, making it an inviting time for beachgoers and outdoor enthusiasts.

Percentage of Sunny Days in September in Cabo Frio

The chart illustrates the percentage of sunny days in Cabo Frio 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 Cabo Frio experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec44%36%56%59%56%61%64%60%48%24%40%46%
Data source: Cabo Frio September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Cabo Frio in September

As the seasons transition in Cabo Frio, Brazil, September marks a pivotal moment where daylight duration settles at 11 hours per day. This is a slight uptick from the shorter days of winter, reflecting the return of warmer months. Following the pattern established earlier in the year, the daylight begins to gradually increase after April’s 11 hours, which is a reminder of the vibrant summer ahead. As daylight elongates toward the end of the year, with November and December basking in the warmth of 13 hours each, September serves as a gentle precursor, inviting residents and visitors to enjoy the lingering light as they transition into the sunny embrace of spring.

Average Daylight Hours in Cabo Frio for September

The chart illustrates the variation in daylight duration in Cabo Frio throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec13h 20m12h 50m12h 11m11h 31m10h 59m10h 44m10h 52m11h 20m11h 57m12h 37m13h 12m13h 30m
Data source: Cabo Frio daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Cabo Frio

As September rolls into Cabo Frio, the refreshing coastal winds continue to dance through the vibrant landscape. With an average wind speed of 7.1 m/s (16 mph), this month maintains a brisk flow reminiscent of August, which recorded the highest gusts of the year. The winds begin to taper off gently into the autumn months, introducing a subtle shift as we approach October, where the average drops to 6.3 m/s (14 mph). Observing the year, it’s clear that Cabo Frio experiences its strongest breezes in the late summer, creating invigorating conditions for beachgoers and water sports enthusiasts alike. This transitional period not only sets the tone for September, but also hints at the calmer currents of the approaching fall season.

Average September Wind Speed in Cabo Frio

The chart displays monthly wind speed patterns in Cabo Frio, 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.
JanFebMarAprMayJunJulAugSepOctNovDec7.34.64.95.84.36.05.67.67.1 m/s6.35.55.1
Data source: Cabo Frio September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Cabo Frio Compares to Other Months

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

September and January showcase distinct weather profiles. In September, temperatures range from a minimum of 19°C (67°F) to a maximum of 26°C (78°F), with an average of 22°C (72°F) and humidity levels at 75%. This month also sees about 41 mm (1.6 in) of precipitation over approximately 5 days. In contrast, January is warmer, featuring temperatures that span from a minimum of 21°C (71°F) to a maximum of 28°C (83°F), with an average of 25°C (77°F) and higher humidity at 85%. Precipitation in January slightly decreases to 38 mm (1.5 in) over 4 days. For more detailed information, check out Cabo Frio weather in January.

September and February present distinct weather patterns in Cabo Frio. In September, temperatures range from a minimum of 19°C (67°F) to a maximum of 26°C (78°F), with an average of 22°C (72°F) and relatively moderate humidity at 75%. The month sees about 41 mm (1.6 in) of precipitation over approximately 5 days. In contrast, February experiences warmer temperatures, with a minimum of 21°C (70°F) and a maximum reaching 29°C (84°F), averaging 25°C (77°F). The precipitation increases to 77 mm (3.0 in) over 9 days, along with higher humidity levels at 86%. For a deeper dive into February weather specifics, check Cabo Frio weather in February.

September and March present distinctly different weather patterns. In September, temperatures range from a minimum of 19°C (67°F) to a comfortable average of 22°C (72°F), peaking at 26°C (78°F). The month sees moderate precipitation, with about 41 mm (1.6 in) falling over 5 days and humidity levels around 75%. In contrast, March is warmer, with minimum temperatures starting at 22°C (72°F) and averaging 25°C (78°F), reaching a high of 29°C (84°F). However, it also brings significantly more rainfall, totaling 126 mm (5.0 in) across 11 days, and higher humidity at 84%. For more detailed insights on the weather during this month, you can check Cabo Frio weather in March.

When comparing the weather in September and April, several key differences emerge. September typically features milder temperatures, with averages around 22°C (72°F) and maximums reaching 26°C (78°F), whereas April enjoys warmer conditions, with average temperatures of 24°C (76°F) and highs of 28°C (83°F). In terms of precipitation, April is notably wetter, receiving 51 mm (2.0 in) over 12 days compared to September's 41 mm (1.6 in) across just 5 days. Additionally, April's humidity is slightly higher at 82%, compared to September's 75%. For more details, check out Cabo Frio weather in April.

September and May exhibit similar minimum temperatures, both starting at around 19°C (67°F). However, May tends to be slightly warmer overall, boasting an average temperature of 23°C (74°F) compared to September's 22°C (72°F). While September experiences less rainfall at 41 mm (1.6 in) across 5 days, May sees increased precipitation at 73 mm (2.9 in) over 9 days. Additionally, humidity levels are a bit higher in May at 80%, compared to September's 75%. For more detailed insights, you can check Cabo Frio weather in May.

When comparing the weather in September and June, we see some interesting similarities and slight variations. Both months have a minimum temperature of 19°C (67°F) and an average temperature around 22°C (72°F). However, June tends to be a bit warmer, with a maximum temperature reaching 27°C (80°F), compared to September's maximum of 26°C (78°F). Additionally, while both months receive the same total precipitation of 41 mm (1.6 in), June has more rainy days, totaling 8 compared to September's 5 days of rain. Humidity levels are also slightly higher in June at 78%, as opposed to September's 75%. For a closer look at June weather, you can check out Cabo Frio weather in June.

When comparing the weather in September and July, both months present a similar range of temperatures, with July having a slightly lower minimum average of 17°C (63°F) compared to September's minimum of 19°C (67°F). The average temperatures are close as well, with September sitting at 22°C (72°F) and July at 21°C (71°F), while the maximum temperatures peak at 26°C (78°F) for both months. Precipitation levels are higher in September, with 41 mm (1.6 in) over 5 days, compared to July's 27 mm (1.1 in) that falls over 6 days. Humidity is slightly lower in September at 75%, compared to July's 77%, making September a bit more comfortable. For more details on July weather, you can check Cabo Frio weather in July.

In comparing the weather of September and August, September offers slightly warmer temperatures, with a minimum of 19°C (67°F) and an average of 22°C (72°F), compared to August's minimum of 17°C (63°F) and average of 21°C (70°F). Both months experience a maximum temperature of 26°C (78°F); however, September has less overall precipitation, totaling 41 mm (1.6 in) over 5 days, while August sees 50 mm (2.0 in) across 9 days. Humidity levels remain consistent at 75% for both months, providing a similarly humid atmosphere. For more detailed insights, you can check Cabo Frio weather in August.

In September, Cabo Frio experiences mild temperatures with a minimum of 19°C (67°F), an average of 22°C (72°F), and a maximum of 26°C (78°F). The month sees moderate precipitation with 41 mm (1.6 in) over 5 days, accompanied by a humidity level of 75%.

In contrast, October's weather remains quite similar, with a minimum temperature of 18°C (64°F), an average of 22°C (73°F), and a slightly warmer maximum of 26°C (79°F). However, October is notably wetter, with 67 mm (2.6 in) of rain over 11 days and a humidity level slightly decreased at 74%. For more detailed insights, you can check Cabo Frio weather in October.

In comparing the weather between September and November, a few notable differences emerge. September typically experiences mild temperatures, with a minimum of 19°C (67°F) and an average around 22°C (72°F), leading to a comfortable maximum of 26°C (78°F). The month also sees relatively low precipitation levels of 41 mm (1.6 in) over about 5 days, along with a humidity of 75%. In contrast, November tends to be slightly warmer, with minimum temperatures rising to 20°C (68°F) and an average of 23°C (73°F), peaking at 27°C (80°F). However, November increases in precipitation significantly, accumulating 109 mm (4.3 in) over 13 days, while humidity also creeps up to 79%. For a detailed look at November weather, you can visit Cabo Frio weather in November.

September and December in Cabo Frio both feature warm temperatures, but December tends to be slightly warmer overall. In September, the temperatures range from a minimum of 19°C (67°F) to a maximum of 26°C (78°F), with an average of 22°C (72°F) and moderate precipitation of 41 mm (1.6 in) over 5 days. In contrast, December sees higher temperatures, with a minimum of 21°C (70°F), an average of 24°C (75°F), and a maximum of 27°C (80°F). However, December also experiences increased rainfall, with 101 mm (4.0 in) spread over 10 days, contributing to a rise in humidity to 81%. For more specifics about the December weather, you can check Cabo Frio weather in December.

Compare Cabo Frio's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Cabo Frio

As September rolls in, Cabo Frio greets visitors with a delightful blend of mild temperatures and refreshing sea breezes, making it a perfect transition from winter to spring. With an average temperature hovering around 22°C (72°F), this month generally feels more temperate than the heat peaks of summer. While the humidity is relatively high at 75%, the chance of rain is minimal, with just a few days of light showers totaling about 41 mm (1.6 in). This charming balance between warmth and occasional moisture sets September apart from the drier and warmer months ahead. For more detailed insights into the weather patterns throughout the year, check out Cabo Frio Climate.