September weather forecast
Batu Apoi, Brunei

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.