nomadseason

December Weather in Isa, Japan

Last updated: August 23, 2025

In December, the average temperature in Isa, Japan hovers around 9°C (48°F). Expect a minimum chill of -1°C (31°F) and a pleasant maximum of 24°C (75°F). During this time, 94 mm (3.7 in) of precipitation typically falls over 8 days, with average humidity at a comforting 74%.

December Temperature in Isa

In December in Isa, the average temperature is 9°C (48°F). The maximum can reach 24°C (75°F) and the minimum can be as low as -1°C (31°F). This weather makes Isa a versatile destination for travelers, offering both mild and cool experiences throughout the month.

December Weather in Isa: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Isa, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Isa, December typically has an average temperature of 9°C (48°F), with highs reaching up to 24°C (75°F) and lows dropping to around -1°C (31°F).
JanFebMarAprMayJunJulAugSepOctNovDec454654606873808277685748
Data source: Temperature data for Isa generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Isa

In Isa in December, the precipitation amount is 94 mm (3.7 in) over the course of 8 days.

December Precipitation Trends in Isa

The chart displays monthly precipitation patterns in Isa, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In Isa, December typically receives around 94 mm (3.7 inches) of precipitation spread over approximately 8 days.
JanFebMarAprMayJunJulAugSepOctNovDec6111016215926138648323425914110294
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

December Humidity in Isa

In Isa in December humidity is 74%. With an average temperature of 9°C (48°F), this humidity feels like a damp chill that seeps into your bones, making travel uncomfortable and necessitating warm layers to fully enjoy your explorations.

December Average Humidity in Isa

This chart illustrates the average monthly humidity levels in Isa, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Isa is approximately 74%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec72%68%72%79%83%86%90%85%80%78%76%75%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Isa

In Isa in December, the maximum UV index reaches 4, which corresponds to a moderate Exposure Category. With a time to burn of 30 minutes, it’s important to take precautions to protect your skin. You can find more details in the Hourly UV Index in Isa for better planning.

Maximum UV Index Levels in Isa for December

The chart shows the monthly maximum UV Index (UVI) for Isa in December, 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 December, the maximum UV index in Isa typically reaches 4, which falls under the moderate exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec569111212121311864
Data source: Isa December 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 December Weather in Isa Compares to Other Months

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

This table compares monthly weather conditions in Isa, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather7°C (45°F)61 mm (2.4 inches)72%moderate
February Weather8°C (47°F)110 mm (4.3 inches)68%high
March Weather12°C (54°F)162 mm (6.4 inches)72%very high
April Weather16°C (61°F)159 mm (6.3 inches)79%extreme
May Weather20°C (68°F)261 mm (10.3 inches)83%extreme
June Weather23°C (74°F)386 mm (15.2 inches)86%extreme
July Weather26°C (80°F)483 mm (19.0 inches)90%extreme
August Weather28°C (82°F)234 mm (9.2 inches)85%extreme
September Weather25°C (77°F)259 mm (10.2 inches)80%extreme
October Weather20°C (69°F)141 mm (5.6 inches)78%very high
November Weather14°C (57°F)102 mm (4.0 inches)76%high
December Weather9°C (48°F)94 mm (3.7 inches)74%moderate

Compare Isa's Climate with Cities Worldwide