September weather forecastBatam, Indonesia

Weather in September

The weather in September in Batam navigates a significant turn, bringing about the driest conditions of the entire year. With mild temperature fluctuation and unchanged humidity, Batam continues to maintain its warm, tropical climate. A substantial decrease lowers the rainfall promptly to 58mm (2.28"), positioning September as a noticeably dry month. With this reduced rainfall, the city enjoys enhanced luminosity courtesy of longer sunshine hours. However, the start of October initiates an increase in rainfall consistent with Batam's return to typical high rainfall levels.

Temperature

The transition into September shows a subtle variation to a still tropical 30.4°C (86.7°F) from August's 30.2°C (86.4°F) in the average high-temperature. In September, a low-temperature average of 26.5°C (79.7°F) is characteristic of Batam, marking a minor shift from daytime temperatures.

Heat index

In September, the average heat index is computed to be a torrid 37°C (98.6°F). Ensure extra safety measures, heat exhaustion and heat cramps are likely. Continuous activity might result in heatstroke.
Know that the heat index computations account for shaded terrains and slight winds. Heat index values might soar by up to 15 Fahrenheit (8 Celsius) degrees with exposure to direct sunshine.
Note: The heat index, also known as 'real feel' or 'feels like', ties air temperature with relative humidity to produce the perceived temperature sensation. One's perception of temperature can vary depending on physical activity and individual heat sensitivity, influenced by factors like wind, attire, and metabolic variations. Consider the fact that direct sun exposure can influence how hot one feels, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Young ones often ignore the need to take a break and drink fluids. Thirst is a late-stage symptom of dehydration - hence, maintaining hydration, particularly during extended physical activities, is crucial.
The body's self-cooling mechanism is rooted in perspiration, where evaporating sweat cools down excessive warmth. In the presence of abundant moisture in the atmosphere, the cooling process through evaporation is hindered, causing the body to feel excessively warm. When body heat isn't effectively managed, risks of dehydration and overheating amplify.

Humidity

In September, the average relative humidity is 73%.

Rainfall

September is the month with the least rainfall. Rain falls for 20 days and accumulates 58mm (2.28") of precipitation.

Daylight

The average length of the day in September is 12h and 7min.
On the first day of September, sunrise is at 05:59 and sunset at 18:07. On the last day of the month, sunrise is at 05:50 and sunset at 17:56 WIB.

Sunshine

In Batam, the average sunshine in September is 10.2h.

UV index

January through December, with an average maximum UV index of 7, are months with the highest UV index. The months with the lowest UV index are January through December, with an average maximum UV index of 7. A UV Index estimate of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for the ordinary person.
Note: In September, a daily UV index of 7 turns into the following recommendations:
Evade overexposure. Individuals with fair skin risk burning in under 20 minutes. Stay out of direct sunlight between 10 a.m. and 4 p.m., when UV radiation is most intense, and remember that not all shade structures provide complete protection. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.