Last updated: August 21, 2025
In September, Guaiba, Brazil, experiences a diverse climate characterized by temperatures ranging from a minimum of 7°C (45°F) to a sweltering maximum of 36°C (96°F), with an average of 18°C (65°F). The month sees moderate rainfall, accumulating to 155 mm (6.1 in) over the course of 12 days, contributing to a high humidity level of 84%. This combination of warmth and moisture creates a unique atmospheric condition that sets the stage for the vibrant transition from winter to spring, making September a noteworthy time for both residents and visitors in Guaiba.
As September rolls into Guaiba, Brazil, temperatures begin to show signs of warming after the cooler winter months. The month starts with a minimum temperature of 7°C (45°F), gradually climbing to an average of 18°C (65°F), while reaching a peak of 36°C (96°F) on the hottest days. This transition marks a noticeable increase from the chilly depths of winter, as September stands out with a more comfortable climate, setting the stage for the approaching summer. The shifting temperatures not only herald the end of cool weather but also invite locals and visitors alike to enjoy outdoor activities in the vibrant atmosphere of Guaiba.
September marks a notable increase in precipitation for Guaíba, Brazil, with a robust 155 mm (6.1 in) of rainfall over 12 days. This uptick follows a relatively dry August, which saw just 70 mm (2.8 in), indicating a significant seasonal shift. As the mid-year dryness gives way to heavier rains, September emerges as one of the wettest months in the region, closely rivaling May's 153 mm (6.0 in). The pattern of increased rainfall suggests a transition to a more humid environment, foreshadowing the wetter months ahead in the calendar. This notable surge highlights the region’s climatic variability, emphasizing September's role as a pivotal month in Guaíba’s precipitation journey.
In Guaíba, Brazil, September marks a notable point in the annual humidity cycle, with levels reaching 84%. This month continues a gradual climb that began in the drier winter months, reflecting the shift towards the more humid conditions of late spring. Following August's humidity of 81%, September's slight increase signifies the onset of warmer weather, as humidity trends steadily rise from 77% in January, peaking at 87% in May. Overall, this pattern showcases the region's characteristic tropical climate, where humidity remains high throughout the year, enhancing both the lush landscapes and vibrant ecosystems of Guaíba.
As the seasons shift in Guaíba, Brazil, the UV Index presents intriguing patterns throughout the year. In September, it rises to a very high level of 9, indicating a significant potential for skin damage with just 15 minutes of unprotected exposure. This spike comes after a period of moderate to high UV levels during the cooler months of June, July, and August, which had UV Indices ranging from 4 to 7. The transition back to very high levels is a precursor to the intense sun of the upcoming summer months, underscoring the crucial importance of sun protection during outdoor activities. For a comprehensive look at UV levels year-round, check out the detailed information at Guaiba UV Index.
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As the vibrant month of September unfolds in Guaiba, Brazil, the sunshine begins to mellow, delivering a total of 228 hours of bright daylight. While this figure marks a slight dip from the sun-drenched peak experienced in the earlier months, it is a gentle transition from the cold winter embrace of the previous month. The trend reveals a gradual decrease in sunlight hours as the region moves into the latter part of the year, with October expected to see a rebound to 274 hours. This natural rhythm underscores a luminous streak throughout the year, with sunshine peaking in December at 361 hours, creating a dynamic yet soothing annual cycle that invites both relaxation and exploration under the Brazilian sky.
As September rolls in, the likelihood of enjoying sunny weather in Guaíba, Brazil, dips to 30%, making it one of the cloudier months of the year. Following the typically warmer and sunnier months of July (60%) and February (59%), the sunshine statistics reflect a noticeable decline. This trend signifies that as winter transitions to spring, Guaíba experiences a shift toward increased cloud cover, contrasting the more favorable sunny days seen in earlier months. Overall, those planning outdoor activities in September should be prepared for a bit of unpredictability—and perhaps keep an umbrella handy!
In September, Guaíba, Brazil, enjoys 11 hours of daylight, marking a subtle transition as the days gradually lengthen towards the end of the year. This month mirrors the daylight duration of August, suggesting a period of stability before the days begin to extend further into the warmer months. As we look at the annual trend, it's fascinating to see how daylight starts at a generous 13 hours in the earlier summer months of January and February, gradually tapering down to 10 hours during the winter months of May through July. After this dip, the days creep back up, signaling the rejuvenation of daylight in spring and a gradual return to 12 hours by October. This rhythmic pattern of daylight not only influences the natural landscape but also enhances the vibrant lifestyle of Guaíba, echoing the changing of the seasons.
As September arrives in Guaiba, Brazil, the winds pick up a refreshing pace, reaching an average speed of 3.3 m/s (7 mph). This month marks a subtle but notable shift, as it stands out with one of the higher wind speeds of the year, just like the coming October. In contrast to the more tranquil breezes of the earlier months, such as March and April, which hover around 2.6 to 2.7 m/s (6 mph), September’s winds usher in a welcome change that hints at the approaching transition into spring. Following September, wind speeds gradually rise, peaking towards the end of the year, suggesting an invigorating trend where the breezes become stronger and more vibrant.
Weather in Guaiba varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Guaiba, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present contrasting weather patterns. In September, temperatures range from a minimum of 7°C (45°F) to a maximum of 36°C (96°F), with an average of 18°C (65°F). This month experiences significant rainfall, totaling 155 mm (6.1 in) over about 12 days, accompanied by high humidity at 84%. In contrast, January sees warmer conditions, with temperatures ranging from a minimum of 15°C (58°F) to a peak of 39°C (103°F), and an average temperature of 26°C (79°F). Precipitation is lower, at 93 mm (3.7 in), also spread over 12 days, but humidity is slightly less, at 77%. For a detailed look at January weather, you can check Guaiba weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a cool 7°C (45°F) to a hot 36°C (96°F), with an average of 18°C (65°F). The month experiences significant precipitation, totaling 155 mm (6.1 in) over 12 days, and humidity sits quite high at 84%. In contrast, February sees milder mornings with minimum temperatures of 14°C (58°F) and an average of 25°C (77°F), peaking at a scorching 38°C (100°F). This month is slightly drier, with 112 mm (4.4 in) of rain over 11 days and lower humidity at 79%. For more detailed insights about February weather patterns, you can visit Guaiba weather in February.
In September, temperatures typically range from a minimum of 7°C (45°F) to a maximum of 36°C (96°F), with an average of 18°C (65°F). The month sees significant precipitation, totaling 155 mm (6.1 in) over approximately 12 days, coupled with high humidity levels of 84%. In contrast, March experiences warmer overall conditions, with a minimum of 13°C (56°F), an average of 23°C (75°F), and highs reaching 38°C (100°F). Rainfall is somewhat less, at 109 mm (4.3 in) over the same number of days, and the humidity is slightly lower at 79%. For more detailed insights, you can check out Guaiba weather in March.
September and April present notable differences in weather patterns. In September, temperatures can range dramatically, with a minimum of 7°C (45°F) and a maximum reaching as high as 36°C (96°F), averaging around 18°C (65°F). This month also sees higher precipitation, totaling 155 mm (6.1 in) over 12 days, coupled with a humidity level of 84%. In contrast, April offers a slightly warmer average temperature of 21°C (71°F), with minimum and maximum temperatures of 8°C (47°F) and 34°C (93°F), respectively. Additionally, April experiences significantly less rainfall, accumulating only 73 mm (2.9 in) over 8 days, and a similar humidity level of 82%. For a deeper look at Guaiba's climate during April, you can check out Guaiba weather in April.
In comparing the weather of September and May, September tends to showcase a wider range of temperatures, with minimums reaching 7°C (45°F) and maximums soaring up to 36°C (96°F), while May features slightly cooler temperatures, with minimums around 5°C (41°F) and maximums peaking at 32°C (90°F). Both months have similar average temperatures, with September averaging 18°C (65°F) and May averaging 17°C (63°F). Precipitation levels are comparable, with September receiving 155 mm (6.1 in) over 12 days and May slightly lower at 153 mm (6.0 in) across 10 days. Humidity is relatively high in both months, with September at 84% and May slightly higher at 87%. For more detailed weather insights specifically for May, you can check Guaiba weather in May.
September and June exhibit notable differences in weather patterns. September experiences a wider temperature range, with minimums around 7°C and maximums soaring up to 36°C, contributing to an average of 18°C. In contrast, June's temperatures are generally milder, with minimums at 3°C and maximums reaching 31°C, resulting in an average of 16°C. Additionally, September tends to have more precipitation, totaling 155 mm over 12 days, compared to June's 113 mm over just 9 days. Both months maintain high humidity levels, with September at 84% and June at 85%. For a more detailed look at June weather in Guaiba, visit Guaiba weather in June.
When comparing the weather in September and July, September tends to exhibit a wider temperature range, with minimums dropping to 7°C (45°F) and maximums soaring up to 36°C (96°F), resulting in an average temperature of 18°C (65°F). In contrast, July sees cooler conditions, with morning lows of 2°C (35°F) and highs reaching only 30°C (87°F), averaging at 14°C (58°F). Additionally, September experiences more precipitation, with 155 mm (6.1 in) falling over 12 days, compared to July's 122 mm (4.8 in) over just 8 days. Both months maintain high humidity levels, hovering around 84% in September and slightly lower at 82% in July. For more specific insights about July weather, you can check Guaiba weather in July.
September's weather is characterized by warmer temperatures compared to August, featuring a minimum of 7°C (45°F) and an average of 18°C (65°F), in contrast to August's minimum of 3°C (38°F) and an average of 16°C (61°F). The maximum temperatures also rise, reaching up to 36°C (96°F) in September, compared to 34°C (94°F) in August. However, September experiences significantly more precipitation, totaling 155 mm (6.1 in) over 12 days, whereas August sees only 70 mm (2.8 in) over 8 days. Additionally, humidity remains relatively high in both months, with September's average at 84% and August at 81%. For more detailed information, you can visit Guaiba weather in August.
September and October show a noticeable transition in weather patterns, with both months experiencing warm conditions. In September, the average temperature rests at 18°C (65°F), while October sees a slight increase to an average of 20°C (68°F). The maximum temperatures remain quite high, peaking at 36°C (96°F) in September and hitting 37°C (100°F) in October. Precipitation levels are relatively similar, with September receiving 155 mm (6.1 in) over 12 days, contrasting slightly with October's 139 mm (5.5 in) across 13 days. Humidity remains stable, with September at 84% and October slightly higher at 85%. For those interested in more details specific to October weather in the region, you can visit Guaiba weather in October.
In September, the weather often features a wide temperature range, with minimums around 7°C (45°F) and soaring daytime highs reaching up to 36°C (96°F). The month experiences considerable rainfall, totaling 155 mm (6.1 in) over approximately 12 days, paired with high humidity levels of 84%. In contrast, November brings slightly warmer conditions, with minimum temperatures around 12°C (53°F) and average highs of 37°C (99°F), while precipitation decreases to 112 mm (4.4 in) over about 10 days. The humidity remains relatively stable at 82%. For a closer look at the weather specifics, you can check Guaiba weather in November.
In September, temperatures in Guaíba range from a low of 7°C (45°F) to a high of 36°C (96°F), with an average temperature of 18°C (65°F). This month sees significant precipitation of 155 mm (6.1 in) over approximately 12 days, contributing to fairly high humidity levels of 84%.
Contrastingly, December experiences warmer weather with minimum temperatures around 13°C (55°F), an average of 24°C (76°F), and highs reaching up to 38°C (101°F). Precipitation decreases to 80 mm (3.2 in) across about 8 days, while humidity remains constant at 84%. For more information about Guaíba's December weather, check out Guaiba weather in December.
As September unfolds in Guaiba, the weather begins to transition from the chilly grasp of winter into the warmth of spring. This month showcases a notable temperature range, with hot days reaching their peak while cool evenings remind us of the winter's tail end. Compared to other months, September's humidity is on the higher side, making the air feel more intense, particularly during those blistering afternoon hours. Though the region sees a fair share of rain, with precipitation spread across several days, it contrasts with the drier, hotter months that follow. The blend of warmth and moisture creates a unique atmosphere, making this transitional period a fascinating time to experience Guaiba's evolving climate. For more insights on the weather patterns throughout the year, visit Guaiba Climate.