Last updated: October 30, 2025
In September, Bandar Seri Begawan experiences a tropical climate characterized by warm temperatures and high humidity. With maximum temperatures reaching 35°C (96°F) and an average of 28°C (83°F), residents and visitors can expect a warm and humid atmosphere, with lows averaging around 23°C (74°F). This month is marked by significant rainfall, totaling approximately 213 mm (8.4 in) over 22 days, making it one of the wetter times of the year. With humidity levels hovering around 85%, the lush greenery of Brunei thrives, providing a vibrant backdrop for those exploring the city during this lush, tropical season.
In September, Bandar Seri Begawan experiences a delightful blend of warm temperatures, with lows averaging around 23°C (74°F) and highs reaching up to 35°C (96°F). This month marks the end of the peak heat seen in the summer, particularly in June, where temperatures hit a sweltering 36°C (97°F). The average temperature maintains a comfortable 28°C (83°F), consistent with the preceding months, reflecting the tropical climate of Brunei. As the transition to the wetter months begins, September's weather remains appealing, inviting both residents and visitors to enjoy outdoor explorations amidst the lush scenery.
September marks a notable peak in precipitation in Bandar Seri Begawan, with an impressive 213 mm (8.4 in) of rain recorded over 22 days. This increase continues the trend observed throughout the year, where the rainy season starts to gain momentum in the latter half. Following a steady rise in rainfall from June's 223 mm to August's 189 mm, September's totals signify a transition into the wetter months of October and November, which typically see even higher averages of 283 mm and 273 mm, respectively. The consistent rain during this month not only reflects the region's tropical climate but also prepares the way for the wettest months ahead, highlighting the dynamic weather patterns characteristic of Brunei Darussalam.
In September, Bandar Seri Begawan experiences a humidity level of 85%, marking a slight increase from the previous month. This trend reflects the city's overall high humidity patterns throughout the year, where levels generally fluctuate between 80% and 87%. As the calendar transitions from the dry months of May and June, which see the lowest humidity, there's a gradual rise leading to September's peak. This pattern suggests a steady atmosphere that can make the tropical climate feel warm and muggy, particularly as the onset of the wetter season approaches. Overall, the persistent humidity levels underscore Brunei's tropical environment, contributing to its lush greenery and vibrant ecosystems.
In September, Bandar Seri Begawan experiences a notably high UV Index of 14, maintaining its classification of extreme exposure, consistent with the previous months' trends. This month marks the continuation of a scorching pattern seen since March, where the UV Index has remained predominantly between 13 and 16, resulting in a rapid burn time of only 10 minutes. As travelers and locals alike enjoy the sunny weather, it's crucial to stay vigilant against sun damage throughout this period. For more detailed information on the UV levels in Bandar Seri Begawan, check out the Bandar Seri Begawan UV Index.
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As September rolls into Bandar Seri Begawan, Brunei Darussalam, the city basks in 273 hours of sunshine, marking a gentle dip from the vibrant summer months. Notably, this transitional period follows a peak in July, which boasts 300 hours of radiant daylight, and maintains a consistent warmth throughout the earlier months of the year, with February and March shining brightly at 271 and 299 hours respectively. While September’s sunlight is slightly less abundant, it encourages a perfect blend of warmth and occasional showers, heralding the onset of the wetter season. This trend of diminishing daylight as the year draws to a close reflects the natural rhythm of life in Brunei, offering a unique charm as the lush landscapes thrive under the lingering sun.
In September, Bandar Seri Begawan experiences a notably low chance of sunny weather, with only an 8% likelihood of sunshine. This marks a dip from the preceding months of July and August, which offer slightly better odds at 15% and 11%, respectively. As the year transitions into the rainier season, the probability of clear skies tends to diminish, making September one of the cloudier months. Thus, if you're planning a visit during this time, it's wise to anticipate some overcast days and prepare for possible rain, as sunny weather becomes less likely in this southeast Asian gem.
As September arrives in Bandar Seri Begawan, Brunei Darussalam, daylight duration remains steady at 12 hours, mirroring the pattern established during the preceding months of April through August. This consistency highlights the region's tropical climate, where daylight hours are relatively uniform throughout the year. Following September, daylight begins to wane slightly, dropping to 11 hours in October, a trend that continues into the later months of the year. This gradual shift indicates the onset of the wet season, yet the extended daylight hours in September allow for ample time to enjoy the vibrant local culture and natural beauty before the shorter days set in.
As September arrives in Bandar Seri Begawan, Brunei Darussalam, the winds whisper at an average speed of 2.1 m/s (5 mph). This gentle breeze mirrors the preceding months, maintaining a consistent flow that has characterized the region since late summer. Notably, September's winds remain steady, reflecting a slight uptick from the calmness felt during the hotter months of June and July. Historically, wind speeds in this tropical paradise fluctuate modestly, with September joining the ranks alongside March and August, creating a tranquil, yet invigorating atmosphere. As the transition to October approaches, one can expect a gradual increase in speed, highlighting the region's unique climatic rhythm and the refreshing embrace of the autumnal shift.
Weather in Bandar Seri Begawan varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Bandar Seri Begawan, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present distinct yet somewhat similar weather patterns. In September, temperatures range from a minimum of 23°C (74°F) to a maximum of 35°C (96°F), with an average of 28°C (83°F). This month experiences significant precipitation, totaling 213 mm (8.4 in) over 22 days, and a high humidity level of 85%. In contrast, January offers slightly cooler temperatures, with a minimum of 23°C (74°F), an average of 27°C (81°F), and a maximum of 32°C (90°F). Additionally, January sees less rainfall, totaling 176 mm (6.9 in) over 21 days, while maintaining a similar humidity level of 86%. For more detailed information on the weather in January, you can check out Bandar Seri Begawan weather in January.
September and February in Bandar Seri Begawan both showcase warm temperatures, but September is notably hotter. In September, the minimum temperature is around 23°C (74°F), with an average of 28°C (83°F) peaking at 35°C (96°F), while February sees slightly cooler averages with a minimum of 23°C (73°F) and a maximum of 33°C (91°F). Additionally, September experiences significantly more rainfall, totaling 213 mm (8.4 in) across 22 days, compared to February’s 98 mm (3.8 in) over 18 days. The humidity levels are relatively high in both months, with September at 85% and February slightly higher at 87%. For a more detailed view, check Bandar Seri Begawan weather in February.
When comparing the weather in September and March, both months exhibit warm temperatures, with September averaging around 28°C (83°F) and March slightly cooler at 27°C (82°F). The minimum temperatures remain consistent at about 23°C (74°F to 75°F), while maximum temperatures peak at 35°C (96°F) in September and 34°C (93°F) in March. However, September is considerably wetter, receiving 213 mm (8.4 in) of precipitation over 22 days, compared to March's 114 mm (4.5 in) over 20 days. Humidity levels are also high in both months, with September at 85% and March slightly higher at 87%. For more detailed information, you can check Bandar Seri Begawan weather in March.
When comparing the weather in September and April, both months feature similar average temperatures, hovering around 28°C (83°F). However, September tends to be slightly more humid with an average humidity of 85%, compared to April's 84%. Precipitation levels in September are also higher, receiving about 213 mm (8.4 in) over 22 days, while April sees around 158 mm (6.2 in) across 21 days. These differences suggest that September may feel a bit more sweltering and rainy than April. For more detailed insights, you can check out Bandar Seri Begawan weather in April.
In comparison to September, May experiences slightly higher minimum temperatures, averaging around 24°C (76°F) compared to September's 23°C (74°F). Both months have the same average temperature of approximately 28°C (83°F), but September tends to have slightly more extreme highs at 35°C (96°F) against May's 35°C (95°F). Precipitation levels are higher in September, with 213 mm (8.4 in) over 22 days, while May sees less rain at 157 mm (6.2 in) spread over 24 days. Additionally, humidity is marginally higher in September at 85% compared to 80% in May. For more specific details on May weather, check out Bandar Seri Begawan weather in May.
When comparing the weather in September and June, both months exhibit similar average temperatures, hovering around 28°C (83°F). However, June tends to be slightly warmer, reaching a maximum of 36°C (97°F) compared to September's peak of 35°C (96°F). Both months experience significant rainfall, with September receiving 213 mm (8.4 in) over 22 days and June slightly wetter at 223 mm (8.8 in) over 21 days. In terms of humidity, September is a bit more humid at 85%, while June's humidity stands at 81%. For more detailed insights, you can check Bandar Seri Begawan weather in June.
In comparing the weather between September and July, both months showcase similar average temperatures, hovering around 28°C (83°F). However, September experiences slightly higher extremes with a minimum of 23°C (74°F) and a maximum of 35°C (96°F), compared to July's minimum of 24°C (75°F) and maximum of 34°C (93°F). Precipitation levels also differ, as September sees a total of 213 mm (8.4 in) over 22 days, while July has slightly less, with 187 mm (7.4 in) over 23 days. The humidity is a bit higher in September at 85%, compared to July’s 80%. For more details, you can visit Bandar Seri Begawan weather in July.
September's weather in Bandar Seri Begawan shows a slight increase in minimum temperature compared to August, with a minimum of 23°C (74°F) versus August's 24°C (76°F). The average temperature remains constant at 28°C (83°F), while the maximum temperature sees a rise to 35°C (96°F) in September, compared to August's peak of 34°C (94°F). Rainfall is more pronounced in September with 213 mm (8.4 in) over 22 days, compared to 189 mm (7.4 in) during the same number of days in August. Humidity is also slightly higher in September at 85%, compared to 82% in August. For more details on the weather conditions, you can refer to Bandar Seri Begawan weather in August.
In September, the temperatures range from a minimum of 23°C (74°F) to a maximum of 35°C (96°F), with an average temperature of 28°C (83°F). The month is characterized by high humidity at 85% and significant rainfall, totaling 213 mm (8.4 in) over 22 days.
In contrast, October sees a slight increase in the minimum temperature to 24°C (75°F), while the average temperature dips a bit to 28°C (82°F) and the maximum temperature reduces to 33°C (92°F). Rainfall is more pronounced, reaching 283 mm (11.1 in) over 27 days, accompanied by a lower humidity level of 81%.
For detailed information on the weather patterns during this month, check out Bandar Seri Begawan weather in October.
In comparing the weather between September and November, we see that both months experience relatively high temperatures, but November maintains slightly cooler averages. September boasts a minimum temperature of 23°C and an average of 28°C, peaking at 35°C, while November starts at a minimum of 24°C with an average of 27°C and a maximum of 32°C. Rainfall increases in November, with 273 mm recorded over 26 days compared to September's 213 mm over 22 days, suggesting a more prolonged wet season. Humidity remains high in both months, slightly decreasing from 85% in September to 81% in November. For a more detailed look at the weather in November, check out Bandar Seri Begawan weather in November.
September and December in Bandar Seri Begawan showcase contrasting yet mild tropical conditions. In September, temperatures peak at a high of 35°C (96°F) with an average of 28°C (83°F), while December's temperatures are slightly cooler with a maximum of 32°C (91°F) and an average of 27°C (81°F). However, December experiences more rainfall, totaling 288 mm (11.3 in) over 29 days, compared to September's 213 mm (8.4 in) on 22 days. Humidity remains high in both months, with September at 85% and December slightly lower at 84%. For a detailed look at the weather conditions during December, you can check the following link: Bandar Seri Begawan weather in December.
As September unfolds in Bandar Seri Begawan, the weather is characterized by a sultry charm, featuring high temperatures that often push towards the upper limits of the spectrum. Unlike the cooler months, this period sees a pronounced increase in humidity, which can feel quite stifling. The frequent downpours, with rain gracing the city on nearly three-quarters of the days, create a lush, vibrant landscape but also remind residents and visitors alike of the tropical climate's intensity. For those looking to understand the broader climate trends throughout the year, diving deeper into the specific patterns can be insightful—explore more at Bandar Seri Begawan Climate.