September Weather in Ondong Siau, Indonesia

Last updated: August 23, 2025

In September, the average temperature in Ondong Siau, Indonesia is a warm 27°C (82°F). Expect pleasant days with a minimum of 25°C (78°F) and a maximum of 29°C (84°F). However, be prepared for occasional rain, as the area sees an average of 170 mm (6.7 in) of precipitation spread over 19 days. With an average humidity of 77%, you'll experience a tropical ambiance perfect for enjoying all that this destination has to offer!

September Temperature in Ondong Siau

In September in Ondong Siau, the average temperature is 27°C (82°F), with maximums reaching up to 29°C (84°F) and minimums dropping to as low as 25°C (78°F). This pleasant and warm weather makes it an ideal time for traveling to enjoy outdoor activities and explore the local attractions.

September Weather in Ondong Siau: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Ondong Siau, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Ondong Siau, September typically has an average temperature of 27°C (82°F), with highs reaching up to 29°C (84°F) and lows dropping to around 25°C (78°F).

Data source: Temperature data for Ondong Siau generated using information from the Copernicus Climate Change Service.

September Precipitation in Ondong Siau

In Ondong Siau in September, the precipitation amount is 170 mm (6.7 in) over the course of 19 days.

September Precipitation Trends in Ondong Siau

The chart displays monthly precipitation patterns in Ondong Siau, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Ondong Siau, September typically receives around 170 mm (6.7 inches) of precipitation spread over approximately 19 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Ondong Siau

In Ondong Siau in September, humidity is 77%. With an average temperature of 27°C (82°F), this humidity feels like a warm blanket wrapping around you, making travel feel heavy and slightly stifling, requiring frequent breaks and hydration to enjoy the sights comfortably.

September Average Humidity in Ondong Siau

This chart illustrates the average monthly humidity levels in Ondong Siau, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Ondong Siau is approximately 77%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Ondong Siau

In Ondong Siau in September, the maximum UV index is 14, which corresponds to an extreme Exposure Category. The time to burn is just 10 minutes, so it's crucial to take precautions. For the detailed hourly UV index in Ondong Siau, you can check here.

Maximum UV Index Levels in Ondong Siau for September

The chart shows the monthly maximum UV Index (UVI) for Ondong Siau in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Ondong Siau typically reaches 14, which falls under the extreme exposure category.

Data source: Ondong Siau September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How September Weather in Ondong Siau Compares to Other Months

Weather in Ondong Siau varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Ondong Siau, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Ondong Siau, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	27°C (81°F)	297 mm (11.7 inches)	78%	extreme
February Weather	27°C (81°F)	172 mm (6.8 inches)	83%	extreme
March Weather	27°C (81°F)	252 mm (9.9 inches)	82%	extreme
April Weather	27°C (82°F)	147 mm (5.8 inches)	80%	extreme
May Weather	28°C (82°F)	212 mm (8.3 inches)	74%	extreme
June Weather	27°C (82°F)	289 mm (11.4 inches)	74%	extreme
July Weather	27°C (82°F)	252 mm (9.9 inches)	75%	extreme
August Weather	28°C (82°F)	182 mm (7.2 inches)	76%	extreme
September Weather	27°C (82°F)	170 mm (6.7 inches)	77%	extreme
October Weather	28°C (82°F)	163 mm (6.4 inches)	75%	extreme
November Weather	27°C (82°F)	259 mm (10.2 inches)	74%	extreme
December Weather	27°C (81°F)	272 mm (10.7 inches)	75%	extreme