September Weather in Isahaya, Japan

Last updated: August 23, 2025

In Isahaya, Japan, the average temperature in September hovers around 25°C (77°F), with a minimum of 19°C (66°F) and a maximum of 32°C (90°F). Expect 225 mm (8.9 in) of precipitation over 14 days, contributing to a high average humidity of 84%. Prepare for a tropical experience!

September Temperature in Isahaya

In September in Isahaya, the average temperature is 25°C (77°F). Maximums can reach 32°C (90°F), and minimums can be as low as 19°C (66°F). This pleasant climate makes Isahaya an ideal destination for travelers seeking comfortable weather.

September Weather in Isahaya: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Isahaya, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Isahaya, September typically has an average temperature of 25°C (77°F), with highs reaching up to 32°C (90°F) and lows dropping to around 19°C (66°F).

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

September Precipitation in Isahaya

In Isahaya in September, the total precipitation amount is 225 mm (8.9 in) spread over the course of 14 days.

September Precipitation Trends in Isahaya

The chart displays monthly precipitation patterns in Isahaya, 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 Isahaya, September typically receives around 225 mm (8.9 inches) of precipitation spread over approximately 14 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 Isahaya

In Isahaya in September, humidity is 84%. With an average temperature of 25°C (77°F), this humidity feels like a warm, enveloping blanket that clings to your skin, making outdoor activities challenging and prompting travelers to seek shade and stay hydrated.

September Average Humidity in Isahaya

This chart illustrates the average monthly humidity levels in Isahaya, 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 Isahaya is approximately 84%, 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 Isahaya

In Isahaya in September, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Isahaya.

Maximum UV Index Levels in Isahaya for September

The chart shows the monthly maximum UV Index (UVI) for Isahaya 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 Isahaya typically reaches 11, which falls under the extreme exposure category.

Data source: Isahaya 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 Isahaya Compares to Other Months

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

This table compares monthly weather conditions in Isahaya, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	8°C (47°F)	61 mm (2.4 inches)	73%	moderate
February Weather	9°C (48°F)	106 mm (4.2 inches)	69%	high
March Weather	12°C (54°F)	157 mm (6.2 inches)	71%	very high
April Weather	15°C (60°F)	143 mm (5.6 inches)	79%	extreme
May Weather	19°C (67°F)	229 mm (9.0 inches)	87%	extreme
June Weather	22°C (73°F)	272 mm (10.7 inches)	91%	extreme
July Weather	26°C (79°F)	442 mm (17.4 inches)	97%	extreme
August Weather	28°C (82°F)	326 mm (12.8 inches)	94%	extreme
September Weather	25°C (77°F)	225 mm (8.9 inches)	84%	extreme
October Weather	20°C (69°F)	117 mm (4.6 inches)	79%	very high
November Weather	15°C (60°F)	81 mm (3.2 inches)	75%	high
December Weather	10°C (51°F)	92 mm (3.6 inches)	72%	moderate