September weather forecastBatu Apoi, Brunei
September
Weather in September
Batu Apoi experiences a subtle shift in weather as September comes to call. The fading heat of the summer gradually gives way to slightly cooler temperatures. Rainfall decreases as dry spells become more frequent. Despite minor shifts in atmospheric pressure and wind speed, the weather remains largely enjoyable. The city experiences improved visibility to 10km (6.2mi) underlining the receding rainfall.Temperature
With September's arrival, Batu Apoi's weather records an average high-temperature of a still tropical 31.9°C (89.4°F), marking little difference from August's 32.2°C (90°F). Throughout the month of September, Batu Apoi sees a steady low-temperature average of 24.2°C (75.6°F).Heat index
The average heat index in September is calculated to be a blistering 43°C (109.4°F). Stay wary: Heat exhaustion and heat cramps are possible. Heatstroke can ensue from extended effort.It is noted that heat index values are ascertained for locations in the shade and with gentle breezes. The direct sunshine could escalate the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', embodies the combination of air temperature and moisture content to illustrate perceived heat. Elements such as metabolic variations, pregnancy, and physical exertion can shape one's weather perception. Under direct sun rays, the felt temperature might be heightened, with the heat index increasing by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly important for children. Young ones are generally at greater risk than adults due to their limited sweating ability. In addition, their large skin surface relative to their small bodies and higher heat production from their activities add to their vulnerability.
By perspiring, the human body can shed its excessive warmth since evaporated sweat cools it off. Under conditions of high relative humidity, the rate of evaporation decreases. This results in the body retaining more heat than under conditions of dry air. Increasing body temperatures can be a precursor to dehydration if the body can't shed the extra heat.
Humidity
The months with the lowest humidity are August and September, with an average relative humidity of 77%.Rainfall
In September, in Batu Apoi, the rain falls for 25.1 days. Throughout September, 103mm (4.06") of precipitation is accumulated. Throughout the year, in Batu Apoi, Brunei, there are 286.2 rainfall days, and 1425mm (56.1") of precipitation is accumulated.Daylight
The average length of the day in September is 12h and 8min.On the first day of September in Batu Apoi, sunrise is at 06:13 and sunset at 18:25. On the last day of the month, sunrise is at 06:06 and sunset at 18:11 +08.
Sunshine
September has the most sunshine of the year in Batu Apoi, with an average of 8.9h of sunshine.UV index
January through December, with an average maximum UV index of 7, are months with the highest UV index in Batu Apoi. January through December, with an average maximum UV index of 7, are months with the lowest UV index. A UV Index value of 6 to 7 symbolizes a high threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum daily UV index, 7 in September, converts into the following recommendations:
Incorporate safeguards and honour sun safety principles. Protection from skin and eye damage is obligatory. Seek shade and limit direct sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Keep in mind that shade structures like parasols or canopies do not offer complete sun protection. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Batu Apoi, Brunei
- Average high temperature in September: 31.9°C
The warmest month (with the highest average high temperature) is May (32.3°C).
The month with the lowest average high temperature is January (29.9°C).
- Average low temperature in September: 24.2°C
The month with the highest average low temperature is May (24.4°C).
The coldest month (with the lowest average low temperature) is March (23.3°C).
Average pressure in September
Batu Apoi, Brunei
- Average pressure in September: 1010.3mbar
The months with the highest atmospheric pressure are February and March (1010.6mbar).
The months with the lowest atmospheric pressure are November and December (1009.4mbar).
Average wind speed in September
Batu Apoi, Brunei
- Average wind speed in September: 6.2km/h
The windiest month (with the highest average wind speed) is February (6.5km/h).
The calmest month (with the lowest average wind speed) is May (5.5km/h).
Average humidity in September
Batu Apoi, Brunei
- Average humidity in September: 77%
The months with the highest relative humidity are January, February, March and December (82%).
The months with the lowest relative humidity are August and September (77%).
Average rainfall in September
Batu Apoi, Brunei
- Average rainfall in September: 103mm
The wettest month (with the highest rainfall) is October (150mm).
The driest month (with the least rainfall) is February (52mm).
Average rainfall days in September
Batu Apoi, Brunei
- Average rainfall days in September: 25.1 days
The month with the highest number of rainy days is October (27.5 days).
The month with the least rainy days is February (16.4 days).
Average daylight in September /
Average sunshine in September
Batu Apoi, Brunei
- Average daylight in September: 12h and 6min
The month with the longest days is June (Average daylight: 12h and 24min).
The month with the shortest days is December (Average daylight: 11h and 54min).
- Average sunshine in September: 8h and 54min
The month with the most sunshine is September (Average sunshine: 8h and 54min).
The month with the least sunshine is January (Average sunshine: 8h and 0min).
Average sunshine days in September
Batu Apoi, Brunei
- Average sunshine days in September: 3.4 days
The month with the most sunshine days is February (10.3 days).
The month with the least sunshine days is November (1.9 days).
Average UV index in September
Batu Apoi, Brunei
- Average UV index in September: 7
The months with the highest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 7).
Average cloud cover in September
Batu Apoi, Brunei
- Average cloud cover in September: 38
The months with the most cloud cover are January and December (Cloud cover 43).
The months with the least cloud cover are August and September (Cloud cover 38).
Average visibility in September
Batu Apoi, Brunei
- Average visibility in September: 10km
The month with the highest visibility is September (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, October, November and December (9km).





