Last updated: August 21, 2025
In September, Oeiras, Brazil experiences warm and dry weather, with maximum temperatures reaching a scorching 40°C (104°F) and an average of 31°C (89°F). The evenings provide a mild relief, with minimum temperatures around 21°C (71°F). Notably, the month sees zero precipitation, resulting in a comfortable humidity level of 51%, making it an ideal time for outdoor activities and exploration. Enjoy the sunny days with clear skies as you soak in the warmth of this vibrant region!
In September, Oeiras, Brazil, embraces the warmth of spring, with temperatures rising to highlight the transition from winter's coolness. The month typically experiences a minimum of 21°C (71°F) and boasts an average of 31°C (89°F), reaching a maximum of 40°C (104°F). This trend marks a steady increase in warmth, as September's averages showcase a notable leap from the cooler months preceding it. With these warm temperatures, locals and visitors alike can revel in the vibrant outdoor activities Oeiras has to offer, all while soaking in the sun’s intensity. As the season unfolds, the climatic shift heralds a lively atmosphere, making September an exciting time in this Brazilian gem.
In Oeiras, Brazil, September marks a striking lull in precipitation, with zero millimeters recorded for the month— a continuation of the dry spell that begins in July and persists through August. This dry stretch contrasts sharply with the earlier months of the year, which see significant rainfall, particularly February with an impressive 217 mm over 21 days. The transition from a wet to a notably dry season highlights a seasonal pattern typical of the region, where precipitation dramatically plummets during the colder months before gradually reemerging in October. Such trends offer valuable insight into Oeiras' climatic rhythm, characterized by significant variability throughout the year.
In September, Oeiras, Brazil experiences a notable shift in humidity, dropping to a comfortable 51%. This decline marks a significant transition from the suffocating highs of summer months, where humidity reached as much as 93% in March. As the region moves into the latter part of the year, the trend continues downward, with humidity further reducing to 45% in October and hitting a low of 41% by November. This gradual decrease heralds the onset of a more pleasant dry season, making September a breath of fresh air after the sweltering peak of summer.
As September arrives in Oeiras, Brazil, the UV Index remains impressively high, measuring 13 on the scale, indicating an extreme exposure category with a quick burn time of just 10 minutes. This follows a trend observed throughout the year, where the UV Index consistently hovers between 11 and 15, emphasizing the need for heightened sun protection. August saw a UV Index of 12, while the months leading up to September showcased values as high as 15 in March. As October approaches, the UV Index slightly steadies at 13, maintaining this pattern of consistent solar intensity. Residents and visitors alike should be mindful of these conditions and take precautions to safeguard their skin. For more details, visit Oeiras UV Index.
UV Risk Categories
September in Oeiras, Brazil, shines with an impressive 344 hours of sunshine, contributing to a vibrant atmosphere as the seasons shift. This point in the year continues a trend of abundant sunlight, following the peak in August with 348 hours. As we move into the final quarter, October takes the sun-drenched lead with 354 hours, but September holds its own, showcasing a distinct consistency in the region's climate. The gradual increase from winter into the spring months highlights a typical Brazilian warmth, making September an ideal time for outdoor activities and enjoying the natural beauty of Oeiras. Overall, the remarkable sunshine patterns throughout these months promise an inviting and lively environment.
In September, Oeiras, Brazil, enjoys a notable likelihood of sunny weather, with the sun shining about 73% of the time. This charming month marks a smooth transition from the vibrant sun-soaked days of August, which boasts an impressive 81% sunshine probability. As the year progresses, September stands out with its reliable forecast, keeping company with the increasingly bright summer months. This trend indicates a steady and pleasant spell of warmth, making September an ideal time for outdoor adventures and basking in the beautiful Brazilian sun.
In Oeiras, Brazil, September marks a refreshing transition as daylight extends to a full 12 hours, aligning with the longer days of the earlier months. After a string of consistent 11-hour days from April through August, the return to a full 12 hours not only brightens the landscape but also reignites the vibrant energy of the local community. This trend of consistent daylight continues into the following months, as both October and November also bask in 12 hours of sunlight. The seasonal rhythm in Oeiras showcases the resilience of daylight, fostering a lively atmosphere and inviting residents and visitors alike to enjoy the sun-drenched days.
As September unfolds in Oeiras, Brazil, the average wind speed settles at a gentle 3.5 m/s (8 mph), reflecting a slight dip from the previous month's breezy 4.6 m/s (10 mph). This marks a transitional moment in the yearly rhythm, as winds begin to ease after the summer’s peak. Observing the seasonal trends, it’s notable that wind speeds have gradually increased from the calmer months of early winter, with July and August showcasing the highest gusts. As we move into October, a further decrease to 2.3 m/s (5 mph) suggests a shift towards the milder conditions of spring. Thus, September serves as a gentle reminder of the changing season, balancing the remnants of summer along with the subtle hints of autumn.
Weather in Oeiras varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Oeiras, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is characterized by high temperatures, with averages reaching 31°C (89°F) and peak highs of 40°C (104°F), accompanied by low humidity levels of 51% and no precipitation. In contrast, January offers a slightly cooler average temperature of 28°C (82°F) with minimums of 22°C (71°F) and maximums up to 39°C (103°F). However, January is markedly wetter, receiving 82 mm (3.2 in) of rainfall over approximately 14 days, coupled with a high humidity level of 90%. For more detailed insights into January’s climate, visit Oeiras weather in January.
September and February exhibit starkly contrasting weather patterns. In September, temperatures soar with a minimum of 21°C (71°F), an average of 31°C (89°F), and a maximum reaching up to 40°C (104°F). The month is characterized by dry conditions, boasting no rainfall and a relatively moderate humidity level of 51%. In contrast, February features milder temperatures, with a minimum of 22°C (72°F), an average of 27°C (81°F), and a maximum of 37°C (98°F). However, February is significantly wetter, receiving 217 mm (8.5 in) of rain over 21 days, accompanied by high humidity at 91%. For more insights into February's weather, check out Oeiras weather in February.
In September, the weather is characterized by high temperatures, with an average of 31°C (89°F) and a maximum reaching up to 40°C (104°F), while enjoying dry conditions with no precipitation and a moderate humidity level of 51%. In stark contrast, March experiences cooler average temperatures of 27°C (81°F) and peaks at 35°C (94°F). Furthermore, March is significantly wetter, with 159 mm (6.3 inches) of rainfall spread across 22 days and a much higher humidity level of 93%. For more detailed insights on March weather, you can visit Oeiras weather in March.
September and April present contrasting weather patterns. In September, temperatures soar with a minimum of 21°C (71°F), averaging 31°C (89°F), and peaking at a scorching 40°C (104°F), accompanied by zero precipitation and a humidity level of 51%. In stark comparison, April features a milder temperature range, with a minimum of 21°C (71°F), an average of 27°C (82°F), and a maximum of 35°C (95°F). However, April is also characterized by significant rainfall, measuring 86 mm (3.4 in) over 14 days, and higher humidity at 92%. For a more detailed look at April's climate, you can check Oeiras weather in April.
In September, the weather is considerably warmer, with average temperatures reaching 31°C (89°F) and maximum highs peaking at 40°C (104°F). This month is characterized by dry conditions, with no recorded precipitation and an average humidity of 51%. In contrast, May experiences slightly cooler temperatures, averaging 29°C (84°F) and maxing out at 37°C (98°F). However, May sees some rain, with 13 mm of precipitation over three days, and higher humidity at 87%. For a closer look at May’s climate specifics, you can visit Oeiras weather in May.
In comparing the weather between September and June, September boasts higher maximum temperatures, reaching up to 40°C (104°F) with an average of 31°C (89°F), while June sees a maximum of 37°C (98°F) and a slightly lower average of 29°C (84°F). However, June experiences more humidity at 77%, compared to September's 51%. Additionally, June has a little bit of precipitation, with 3 mm (0.1 in), while September remains completely dry with no recorded precipitation. For more details on June weather, visit Oeiras weather in June.
In September, the weather is generally hotter and more humid compared to July, with average temperatures reaching up to 31°C (89°F) and maximums soaring to 40°C (104°F). Conversely, July features slightly cooler average temperatures at 29°C (84°F), peaking at 38°C (101°F), but with higher humidity levels at 66%. Interestingly, both months experience no precipitation, making them dry periods. For more detailed weather insights, you can check Oeiras weather in July.
In September, the weather in Oeiras shows a slight warming trend compared to August, with minimum temperatures of 21°C (71°F) and maximums reaching 40°C (104°F), compared to 20°C (68°F) and a peak of 38°C (101°F) in August. The average temperature also increases to 31°C (89°F) in September, up from 30°C (86°F) the previous month. Both months experienced no precipitation; however, humidity levels are lower in September at 51%, while August had a higher humidity of 58%. For more details on August's weather, check out Oeiras weather in August.
September weather is characterized by high temperatures, with daily averages reaching 31°C (89°F) and a maximum of 40°C (104°F), while remaining completely dry with no recorded precipitation. The humidity sits at 51%, making the heat feel quite intense. In contrast, October sees a slight increase in minimum temperature to 23°C (74°F) and an average temperature of 32°C (90°F), but it retains the upper limit of 40°C (104°F). Notably, October experiences some rainfall, with 20 mm (0.8 in) spread over two days, which contributes to a drop in humidity to 45%. For more detailed information, check out Oeiras weather in October.
In September, the weather is typically very warm, with average temperatures ranging from a minimum of 21°C (71°F) to a maximum of 40°C (104°F), and no recorded precipitation, resulting in a humidity level of 51%. In contrast, November experiences slightly cooler conditions, with temperatures ranging from a low of 22°C (72°F) to a high of 39°C (103°F). However, this month sees a shift in weather patterns, bringing around 51 mm (2.0 in) of precipitation over approximately 6 days and lower humidity at 41%. For more detailed information on November weather in Oeiras, you can check this link: Oeiras weather in November.
In September, the weather is characterized by higher temperatures, with a minimum of 21°C (71°F) and an average of 31°C (89°F), peaking at a scorching 40°C (104°F). The month is dry, featuring no precipitation and relatively low humidity at 51%. In contrast, December sees a slight increase in minimum temperature at 22°C (72°F) and a decrease in average temperature to 29°C (84°F), with a maximum of 39°C (102°F). However, December is substantially wetter, recording 81 mm (3.2 in) of precipitation over 10 rainy days and higher humidity at 67%. For more detailed information, you can explore Oeiras weather in December.
In September, Oeiras welcomes a distinctly dry and warm climate, setting it apart from other months of the year. With maximum temperatures soaring up to 40°C and an average hovering around a comfortable 31°C, it's a great time to enjoy the sun without the worry of rain, as precipitation is virtually absent. The humidity remains manageable at 51%, making the heat more bearable than in the peak of summer. For those planning a visit or simply curious about the regional weather patterns, September's standout conditions promise a delightful experience. For more insights into the weather throughout the year, check out the detailed Oeiras Climate.