September Weather in Santos, Brazil

Last updated: August 21, 2025

In Santos, Brazil, the weather in September showcases a dynamic blend of warm temperatures and notable humidity. With a maximum of 33°C (92°F) and an average of 21°C (70°F), the month offers pleasant warmth tempered by refreshing coastal breezes. However, visitors should prepare for an occasional downpour, as 102 mm (4.0 in) of rain falls over approximately 13 days, contributing to a humidity level of 78%. This combination creates a tropical atmosphere, making September an ideal time for beachgoers and adventurers alike to experience the vibrant culture and scenery of Santos.

September Temperature in Santos

In September, Santos experiences a gradual transition into warmer summer temperatures, with minimums around 15°C (60°F) and average daytime highs peaking at an inviting 33°C (92°F). This month marks a notable shift from the cooler winter months, especially with the average temperature rising to a comfortable 21°C (70°F), encouraging outdoor activities along the stunning coastline. As the ocean breeze mingles with the warm air, visitors can relish in the vibrant atmosphere that blossoms this time of year. The warmth of September sets the stage for the approaching summer, making it an ideal month for beach lovers and those seeking the sun’s embrace.

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

The chart illustrates September temperature patterns in Santos, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Santos, 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).
JanFebMarAprMayJunJulAugSepOctNovDec787777747170676769717275
Data source: Temperature data for Santos 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 Santos

In September, Santos, Brazil experiences a moderate precipitation of 102 mm (4.0 in), falling on an average of 13 days throughout the month. This represents a slight decline in rainfall compared to the wetter months of February and March, where totals peaked at 249 mm (9.8 in) and 229 mm (9.0 in), respectively. Interestingly, September's precipitation aligns with the drier patterns observed during the previous months of June and July, which recorded only 117 mm (4.6 in) and 81 mm (3.2 in), respectively. This consistent drop in rainfall suggests a transition into the drier season as Santos approaches the more humid and rainier months ahead, sparking anticipation for the vibrant blooms of spring that typically follow.

September Precipitation Trends in Santos

The chart displays monthly precipitation patterns in Santos, 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 Santos, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec18424922913913011781134102183147153
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Santos

In September, Santos, Brazil experiences a humidity level of 78%, which continues the trend of gradually decreasing moisture from the peak levels seen earlier in the year. After starting with a high of 89% in January, humidity has steadily declined over the months, reaching its lowest point of 76% in October. This slight relief in humidity during September hints at the changing seasons, offering a brief respite before the wetter months of November and December, which see numbers climb back to 85% and 87%, respectively. Overall, the trend reflects a marked shift from the sultry summer months to a more temperate early fall, setting the stage for the return of higher humidity levels as the year progresses.

September Average Humidity in Santos

This chart illustrates the average monthly humidity levels in Santos, 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 Santos is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec89%87%86%84%84%82%80%78%78%76%85%87%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Santos

In September, Santos, Brazil, experiences a UV Index of 11, categorized as extreme, with a burn time of just 10 minutes. This month marks a transition into higher UV levels as it echoes the patterns observed earlier in the year, where the UV Index consistently peaks during the summer months. With values fluctuating between 6 to 15 throughout the year, it’s crucial for residents and visitors alike to remain vigilant, especially in months like September, when sun exposure can lead to skin damage in mere minutes. As the sun's intensity ramps up heading into the spring, it serves as a reminder to take proper sun safety precautions. For more detailed weather insights, check out the comprehensive guide on the Santos UV Index.

Maximum UV Index Levels in Santos for September

The chart shows the monthly maximum UV Index (UVI) for Santos 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 Santos typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec15141211866911131415
Data source: Santos 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 Santos

As summer transitions to spring in Santos, Brazil, September brings a pleasant 274 hours of sunshine, maintaining the steady glow of the preceding months. Following a peak in March with 298 hours, sunshine hours dip slightly over the year, reflecting the natural ebb and flow of seasonal changes. However, September’s sunshine mirrors the robust hours seen in May and July, offering a delightful blend of warmth and brightness. This month typically serves as a precursor to the even sunnier days of late spring and early summer; with October promising 261 hours, the anticipation of longer, sun-drenched days lies just ahead. Overall, the gradual transition underscores Santos' reputation for vibrant coastal weather, inviting locals and travelers alike to bask in its golden rays.

Monthly Sunshine Duration in Santos: September Highlighted

The September sunshine duration represents the total number of hours Santos 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.
JanFebMarAprMayJunJulAugSepOctNovDec256h265h298h291h274h243h275h250h274h261h295h317h
Data source: Santos September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Santos During September

In Santos, Brazil, the likelihood of sunny weather in September stands at 37%, marking a notable shift as the city transitions from the relatively warmer months of July and August, which boast higher chances of sunshine at 61% and 50%, respectively. Following a summer peak, September’s chance of sun dips, reflecting a gradual move towards the rainy season, where October sees a further decline to just 21%. Despite the drop, the September sun still invites visitors to enjoy the mild climate and picturesque coastal views, making it a charming time to explore the vibrant city before the more overcast days set in later in the year.

Percentage of Sunny Days in September in Santos

The chart illustrates the percentage of sunny days in Santos 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 Santos experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec16%43%42%49%47%40%61%50%37%21%42%42%
Data source: Santos September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Santos in September

As the calendar turns to September in Santos, Brazil, daylight lingers pleasantly with 11 hours of sunshine each day. This marks a subtle yet notable shift, maintaining the daylight duration seen in August. As the year progresses, the trend of diminishing daylight begins to balance, transitioning from the lengthy days of summer and approaching the shorter days of winter. The daylight hours gradually decline from a peak of 13 hours in January to their nadir of 10 hours between May and July, before nudging upwards again. As October approaches, Santos will enjoy an increase back to 12 hours of daylight, a comforting reminder of the vibrant seasons ahead.

Average Daylight Hours in Santos for September

The chart illustrates the variation in daylight duration in Santos throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec13h 24m12h 52m12h 11m11h 29m10h 56m10h 39m10h 48m11h 18m11h 57m12h 39m13h 15m13h 34m
Data source: Santos daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Santos

As September rolls into Santos, Brazil, the winds begin to pick up, with an average speed of 3.8 m/s (9 mph). This gentle breeze follows a trend of increasing winds that starts in late summer, culminating in October’s brisk 4.7 m/s (11 mph). While earlier months exhibited relatively calm conditions, September’s winds signal the transition into a more dynamic season. This subtle rise contributes to the invigorating atmosphere of the coast, setting the stage for the bustling activities that the spring months bring. As the winds shift from the lighter summer breezes, they breathe life into the city, creating the perfect setting for outdoor adventures and seaside relaxation.

Average September Wind Speed in Santos

The chart displays monthly wind speed patterns in Santos, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.82.72.63.63.33.23.23.93.8 m/s4.73.73.4
Data source: Santos September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Santos Compares to Other Months

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

September and January present contrasting weather patterns. In September, temperatures range from a comfortable 15°C (60°F) to a warm 33°C (92°F), with an average of 21°C (70°F). The month sees about 102 mm (4.0 in) of precipitation over 13 days, accompanied by a humidity level of 78%. In contrast, January experiences warmer temperatures, with a minimum of 21°C (69°F) and a maximum of 32°C (90°F), averaging 26°C (79°F). However, it is also wetter, receiving 184 mm (7.2 in) of rainfall across 18 days and higher humidity at 89%. For a detailed look at January's weather, visit Santos weather in January.

In comparing the weather between September and February, it's evident that February experiences slightly warmer temperatures, with an average of 25°C (78°F) compared to September's average of 21°C (70°F). Both months can reach a maximum of 33°C (91°F), but September tends to start cooler with a minimum temperature of 15°C (60°F), while February has a minimum of 21°C (69°F). Additionally, February sees significantly more rainfall, with 249 mm (9.8 in) over 19 days, in contrast to September's 102 mm (4.0 in) over 13 days. The humidity levels are also higher in February at 87%, compared to 78% in September. For more detailed information on February weather, you can check Santos weather in February.

In September, temperatures range from a pleasant minimum of 15°C (60°F) to a maximum of 33°C (92°F), with an average of 21°C (70°F). The month experiences about 102 mm (4.0 in) of precipitation spread across 13 days, coupled with a humidity level of 78%. In contrast, March tends to be warmer, with temperatures starting at a minimum of 21°C (69°F) and peaking at 32°C (90°F), averaging 25°C (77°F). However, it is significantly wetter, receiving 229 mm (9.0 in) of rainfall over 20 days, along with higher humidity levels of 86%. This difference highlights the transition from the drier, warmer days of September to the wetter, more humid days of March. For more detailed insights into March’s weather, you can check Santos weather in March.

September and April present noticeable differences in weather patterns. In September, temperatures range from a minimum of 15°C (60°F) to a maximum of 33°C (92°F), with an average of 21°C (70°F). Conversely, April tends to be slightly warmer, with temperatures starting at 19°C (66°F) and peaking at 31°C (89°F), averaging around 23°C (74°F). Precipitation levels are also higher in April, totaling 139 mm (5.5 in) over 15 days, compared to September’s 102 mm (4.0 in) in 13 days. Additionally, April exhibits a higher humidity level at 84%, compared to September’s 78%. For more information on the weather specifics in April, you can visit Santos weather in April.

In comparing the weather between September and May, both months exhibit warm temperatures, with September averaging around 21°C (70°F) and May slightly warmer at 22°C (71°F). Interestingly, both months share a minimum temperature of around 15°C (60°F), but September can see a higher maximum temperature of 33°C (92°F), contrasting with May's peak of 29°C (84°F). Precipitation is prevalent in both months, with September receiving 102 mm (4.0 in) and May a bit wetter at 130 mm (5.1 in), experienced on 13 days in each month. In terms of humidity, September has a level of 78%, while May is slightly more humid at 84%. For those interested in the specifics of May weather, check out Santos weather in May.

In both September and June, temperatures show a similar range, with minimums around 15°C (60°F) and average temperatures hovering near 21°C (70°F). However, September can see slightly higher maximum temperatures, peaking at 33°C (92°F), while June's maximum is slightly lower at 30°C (86°F). Rainfall in June is a bit heavier than in September, with total precipitation of 117 mm (4.6 in) over 12 days compared to September's 102 mm (4.0 in) over 13 days. Humidity is slightly higher in June at 82% versus September's 78%. For more details, check out Santos weather in June.

In comparing the weather of September and July, we observe that September tends to be warmer, with average temperatures reaching 21°C (70°F) compared to July’s average of 20°C (67°F). September also sees a higher maximum temperature of 33°C (92°F), whereas July peaks at 30°C (86°F). On the precipitation front, September is wetter, accumulating 102 mm (4.0 in) over 13 days, compared to July's 81 mm (3.2 in) over just 8 days. Humidity levels are slightly higher in September at 78%, compared to 80% in July, making July feel a bit more comfortable overall. For a more detailed look at July weather patterns, you can check Santos weather in July.

In comparing the weather conditions of August and September, it's evident that September experiences slightly warmer temperatures overall, with an average of 21°C (70°F) compared to August's average of 19°C (67°F). The maximum temperatures also rise from 30°C (87°F) in August to 33°C (92°F) in September, indicating a transition to hotter days. However, September has slightly less precipitation than August, receiving 102 mm (4.0 in) over the same number of rainy days, 13. Both months maintain consistent humidity levels at 78%. For a closer look at August's weather specifics, you can visit Santos weather in August.

In September, temperatures in Santos range from a minimum of 15°C (60°F) to a maximum of 33°C (92°F), with an average temperature of 21°C (70°F). The month experiences 102 mm (4.0 in) of precipitation over 13 days, accompanied by humidity levels around 78%. In contrast, October brings slightly warmer temperatures, with lows of 17°C (62°F) and highs reaching 34°C (93°F), along with an average temperature of 22°C (72°F). However, it also sees a significant increase in rainfall, accumulating 183 mm (7.2 in) over 19 days, while humidity decreases slightly to 76%. For more detailed information about October weather in Santos, you can visit Santos weather in October.

In September, temperatures in Santos range from a minimum of 15°C (60°F) to a maximum of 33°C (92°F), with an average temperature of 21°C (70°F). The month experiences 102 mm (4.0 in) of precipitation over about 13 days, and humidity levels are relatively high at 78%. In contrast, November sees slightly warmer temperatures, with a minimum of 17°C (63°F), an average of 22°C (72°F), and a maximum of 31°C (87°F). However, November also brings increased rainfall, totaling 147 mm (5.8 in) spread over 18 days, alongside a rise in humidity to 85%. This shift highlights a transition from the warmer, drier days of September to the more humid and wetter conditions typical of November. For a more detailed look at November weather, visit Santos weather in November.

When comparing the weather in September to December, there are notable differences in temperature, precipitation, and humidity. In September, temperatures range from a minimum of 15°C (60°F) to a maximum of 33°C (92°F), with an average of 21°C (70°F). By December, the climate is warmer, featuring a minimum of 19°C (66°F), an average of 24°C (75°F), and a maximum of 30°C (87°F). Precipitation increases from 102 mm (4.0 in) over 13 days in September to 153 mm (6.0 in) over 19 days in December, contributing to a higher humidity level of 87% in the latter month. For more specific insights into December weather, you can visit Santos weather in December.

Compare Santos's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Santos

As September rolls in, Santos experiences a delightful transition in weather compared to the cold, damp winter months. With temperatures averaging 21°C (70°F) and peaking at a warm 33°C (92°F), the city greets springtime with open arms. However, this month also brings a fair share of rain, as evidenced by 102 mm of precipitation over 13 days, contributing to a humidity level of 78% that adds a tropical feel to the pleasant warmth. If you're planning a visit, this blend of warmth and occasional showers marks September as a unique time to experience Santos, distinctly different from the more stable weather patterns in the summer months. For a deeper understanding of the yearly variations, check out Santos Climate.