Last updated: August 23, 2025
In December, the average temperature in Nagaoka, Japan hovers around 5°C (41°F), making it a cool yet inviting time of year. Temperatures can dip as low as -5°C (23°F) and reach a pleasant 20°C (68°F), offering a wide range of experiences. Expect approximately 204 mm (8.0 in) of precipitation over 25 days, resulting in a notably high average humidity of 86%. Whether you're exploring the city or enjoying the outdoors, be prepared for a variety of weather conditions!
In December in Nagaoka, the average temperature is 5°C (41°F), with maximums reaching up to 20°C (68°F) and minimums dropping as low as -5°C (23°F). Be prepared for varying weather conditions during your travels, as it's wise to pack layers to stay comfortable.
In Nagaoka in December, the precipitation amount is 204 mm (8.0 in) spread over 25 days.
In Nagaoka in December humidity is 86%. With an average temperature of 5°C (41°F), this humidity feels like a heavy, damp blanket wrapping around you, making outdoor activities uncomfortable and travel quite challenging due to the chill combined with the stickiness in the air.
In Nagaoka in December, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Nagaoka, you can check the information here.
UV Risk Categories
Weather in Nagaoka varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Nagaoka, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 2°C (37°F) | 165 mm (6.5 inches) | 88% | moderate |
| February Weather | 3°C (38°F) | 138 mm (5.4 inches) | 86% | moderate |
| March Weather | 7°C (45°F) | 130 mm (5.1 inches) | 81% | high |
| April Weather | 12°C (53°F) | 114 mm (4.5 inches) | 78% | very high |
| May Weather | 18°C (64°F) | 110 mm (4.3 inches) | 81% | very high |
| June Weather | 21°C (71°F) | 108 mm (4.3 inches) | 88% | very high |
| July Weather | 26°C (79°F) | 283 mm (11.2 inches) | 92% | extreme |
| August Weather | 27°C (82°F) | 186 mm (7.3 inches) | 92% | extreme |
| September Weather | 23°C (73°F) | 151 mm (5.9 inches) | 89% | very high |
| October Weather | 17°C (63°F) | 158 mm (6.2 inches) | 87% | high |
| November Weather | 11°C (52°F) | 139 mm (5.5 inches) | 85% | moderate |
| December Weather | 5°C (41°F) | 204 mm (8.0 inches) | 86% | moderate |