September weather forecastSerang, Indonesia
September
Weather in September
With September, the dry spell fades and Serang’s rainy season re-emerges. Rainfall measures an average of 27mm (1.06"), marking the city’s transition into its wetter season. Despite the increase in rain, the city's temperatures and humidity levels remain steady, providing a familiar ambiance. Come October, the city’s precipitation levels climb further, ushering in heavier rainfall.Temperature
A minor adjustment in Serang's average high-temperature is noted with the start of September, touching a still hot 31.2°C (88.2°F) from August's 30.7°C (87.3°F). An average nighttime temperature of 24.9°C (76.8°F) is recorded in Serang, Indonesia, during September.Heat index
The heat index value during September is evaluated at a very hot 38°C (100.4°F). Take special precautions - heat exhaustion and heat cramps are expected. Heatstroke may occur with lengthy activity.Understanding the heat index involves considering values for shaded locales with light wind. Direct sunlight might cause an increase of up to 15 Fahrenheit (8 Celsius) degrees in the heat index.
Note: The heat index, also known as 'apparent temperature' or 'feels like', is an indicator that blends the effects of temperature and humidity to depict perceived warmth. Additional factors encompassing metabolic differences, the level of physical activity, and clothing can impact the individual's perception of temperature. One must note that being under the direct sun can escalate the heat's effects, with the heat index possibly rising by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly meaningful for babies and toddlers. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.
One of the main methods the human body employs to cool down is by perspiring, as this process allows sweat to evaporate and remove excess heat. Increased relative humidity interferes with body cooling by slowing the rate of evaporation, resulting in a slower body cooling rate and a heightened feeling of heat. As the body gains more heat than it can dissipate, there's a risk of increasing temperatures and resultant overheating.
Humidity
The months with the lowest humidity in Serang, Indonesia, are September and October, with an average relative humidity of 71%.Rainfall
September is the month with the least rainfall in Serang. Rain falls for 11.9 days and accumulates 27mm (1.06") of precipitation.Daylight
The average length of the day in September is 12h and 4min.On the first day of the month, sunrise is at 05:55 and sunset at 17:55. On the last day of September, sunrise is at 05:40 and sunset at 17:49 WIB.
Sunshine
With an average of 9.4h of sunshine, September has the most sunshine of the year.UV index
The months with the highest UV index in Serang are January through December, with an average maximum UV index of 7. January through December, with an average maximum UV index of 7, are months with the lowest UV index in Serang. A UV Index of 6 to 7 symbolizes a high health vulnerability from unsafe exposure to UV radiation for average individuals.Note: In September, the maximum UV index of 7 suggests this advice:
Persist with safeguards and heed sun safety doctrines. Keeping sunburn at bay is of prime importance. 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. For optimum UV protection, wear sun-resistant attire complemented with a hat and quality shades.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Serang, Indonesia
- Average high temperature in September: 31.2°C
The warmest month (with the highest average high temperature) is October (31.6°C).
The month with the lowest average high temperature is January (29.6°C).
- Average low temperature in September: 24.9°C
The months with the highest average low temperature are May and November (26°C).
The coldest month (with the lowest average low temperature) is August (24.5°C).
Average pressure in September
Serang, Indonesia
- Average pressure in September: 1011.1mbar
The month with the highest atmospheric pressure is September (1011.1mbar).
The month with the lowest atmospheric pressure is December (1009.2mbar).
Average wind speed in September
Serang, Indonesia
- Average wind speed in September: 6.2km/h
The windiest months (with the highest average wind speed) are January and December (11.3km/h).
The calmest month (with the lowest average wind speed) is September (6.2km/h).
Average humidity in September
Serang, Indonesia
- Average humidity in September: 71%
The months with the highest relative humidity are February and March (78%).
The months with the lowest relative humidity are September and October (71%).
Average rainfall in September
Serang, Indonesia
- Average rainfall in September: 27mm
The wettest months (with the highest rainfall) are January and February (180mm).
The driest month (with the least rainfall) is September (27mm).
Average rainfall days in September
Serang, Indonesia
- Average rainfall days in September: 11.9 days
The month with the highest number of rainy days is January (28.8 days).
The month with the least rainy days is August (11.3 days).
Average daylight in September /
Average sunshine in September
Serang, Indonesia
- Average daylight in September: 12h and 6min
The month with the longest days is December (Average daylight: 12h and 30min).
The month with the shortest days is June (Average daylight: 11h and 48min).
- Average sunshine in September: 9h and 24min
The month with the most sunshine is September (Average sunshine: 9h and 24min).
The months with the least sunshine are June and July (Average sunshine: 7h and 12min).
Average sunshine days in September
Serang, Indonesia
- Average sunshine days in September: 16.3 days
The month with the most sunshine days is August (16.9 days).
The month with the least sunshine days is January (0.6 days).
Average UV index in September
Serang, Indonesia
- 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
Serang, Indonesia
- Average cloud cover in September: 23
The month with the most cloud cover is January (Cloud cover 49).
The months with the least cloud cover are August and September (Cloud cover 23).
Average visibility in September
Serang, Indonesia
- Average visibility in September: 10km
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (10km).
The month with the lowest visibility is January (9km).





