May Weather in Kosai, Japan

Last updated: August 23, 2025

In Kosai, Japan, the average temperature in May hovers around 20°C (69°F), with temperatures ranging from a cool 9°C (48°F) to a warm 32°C (89°F). Visitors can expect 187 mm (7.4 in) of precipitation over approximately 11 days, contributing to an average humidity level of 83%. Whether you’re bracing for a chilly day or a sun-soaked afternoon, be prepared for the diverse weather conditions!

May Temperature in Kosai

In May in Kosai, the average temperature is 20°C (69°F). Maximum temperatures can reach 32°C (89°F), while minimums can drop as low as 9°C (48°F). It's a great time to visit for those who enjoy mild weather with a chance for warmer days.

May Weather in Kosai: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Kosai, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Kosai, May typically has an average temperature of 20°C (69°F), with highs reaching up to 32°C (89°F) and lows dropping to around 9°C (48°F).

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

May Precipitation in Kosai

In Kosai, in May, the precipitation amount is 187 mm (7.4 in) spread over 11 days.

May Precipitation Trends in Kosai

The chart displays monthly precipitation patterns in Kosai, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Kosai, May typically receives around 187 mm (7.4 inches) of precipitation spread over approximately 11 days.

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

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Millimeters (mm) Inches (in)

May Humidity in Kosai

In Kosai in May, humidity is 83%. With an average temperature of 20°C (69°F), this humidity feels like a warm embrace, making every step slightly more laborious and the air thick with moisture, which can be quite stifling for traveling.

May Average Humidity in Kosai

This chart illustrates the average monthly humidity levels in Kosai, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Kosai is approximately 83%, offering insight into how humid the weather typically is during this month.

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

May UV Index in Kosai

In Kosai in May, 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 Kosai.

Maximum UV Index Levels in Kosai for May

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

Data source: Kosai May 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 May Weather in Kosai Compares to Other Months

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

This table compares monthly weather conditions in Kosai, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	6°C (44°F)	49 mm (1.9 inches)	82%	moderate
February Weather	7°C (45°F)	69 mm (2.7 inches)	79%	moderate
March Weather	12°C (53°F)	154 mm (6.1 inches)	74%	very high
April Weather	16°C (60°F)	160 mm (6.3 inches)	76%	very high
May Weather	20°C (69°F)	187 mm (7.4 inches)	83%	extreme
June Weather	23°C (74°F)	240 mm (9.4 inches)	87%	extreme
July Weather	27°C (81°F)	385 mm (15.2 inches)	93%	extreme
August Weather	29°C (85°F)	189 mm (7.4 inches)	91%	extreme
September Weather	25°C (78°F)	217 mm (8.5 inches)	87%	very high
October Weather	20°C (68°F)	284 mm (11.2 inches)	85%	high
November Weather	14°C (58°F)	75 mm (2.9 inches)	83%	moderate
December Weather	9°C (48°F)	65 mm (2.6 inches)	83%	moderate