May Weather in Iiyama, Japan

Last updated: August 23, 2025

In Iiyama, Japan, the average temperature in May hovers around 15°C (59°F). During this time, temperatures can dip as low as 0°C (33°F) and soar to a maximum of 31°C (88°F). Expect about 160 mm (6.3 in) of precipitation spread over 16 days, contributing to an average humidity level of 81%.

May Temperature in Iiyama

In May in Iiyama, the average temperature is 15°C (59°F), with maximums reaching up to 31°C (88°F) and minimums dropping as low as 0°C (33°F). This varied climate makes Iiyama an ideal destination for travelers seeking both mild and warm weather experiences.

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

The chart illustrates May temperature patterns in Iiyama, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Iiyama, May typically has an average temperature of 15°C (59°F), with highs reaching up to 31°C (88°F) and lows dropping to around 0°C (33°F).

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

May Precipitation in Iiyama

In Iiyama in May, the total precipitation amount is 160 mm (6.3 in) spread over 16 days.

May Precipitation Trends in Iiyama

The chart displays monthly precipitation patterns in Iiyama, 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 Iiyama, May typically receives around 160 mm (6.3 inches) of precipitation spread over approximately 16 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 Iiyama

In Iiyama in May humidity is 81%. With an average temperature of 15°C (59°F), this humidity feels like a heavy blanket draped over you, making traveling quite uncomfortable as you constantly wipe away beads of sweat and feel the stickiness clinging to your clothes.

May Average Humidity in Iiyama

This chart illustrates the average monthly humidity levels in Iiyama, 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 Iiyama is approximately 81%, 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 Iiyama

In Iiyama 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 Iiyama.

Maximum UV Index Levels in Iiyama for May

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

Data source: Iiyama 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 Iiyama Compares to Other Months

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

This table compares monthly weather conditions in Iiyama, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-2°C (29°F)	144 mm (5.7 inches)	88%	moderate
February Weather	-1°C (30°F)	129 mm (5.1 inches)	86%	high
March Weather	4°C (39°F)	133 mm (5.2 inches)	81%	very high
April Weather	9°C (48°F)	141 mm (5.5 inches)	78%	very high
May Weather	15°C (59°F)	160 mm (6.3 inches)	81%	extreme
June Weather	18°C (65°F)	171 mm (6.7 inches)	88%	extreme
July Weather	22°C (73°F)	341 mm (13.4 inches)	92%	extreme
August Weather	24°C (75°F)	198 mm (7.8 inches)	92%	extreme
September Weather	19°C (67°F)	194 mm (7.6 inches)	89%	very high
October Weather	13°C (56°F)	217 mm (8.5 inches)	87%	high
November Weather	7°C (44°F)	94 mm (3.7 inches)	85%	moderate
December Weather	1°C (34°F)	151 mm (6.0 inches)	86%	moderate