Last updated: June 24, 2025
In December, the average temperature in Castlewood, United States hovers around -5°C (24°F). Expect chilly lows plummeting to -26°C (-14°F) and an occasional warm day peaking at 13°C (56°F). During this time, precipitation amounts to 31 mm (1.2 in) spread over 5 days, while the air maintains a damp humidity level of 84%. Stay prepared for the wintery conditions!
In December in Castlewood, the average temperature is -5°C (24°F), with a maximum that can reach 13°C (56°F) and a minimum that can drop as low as -26°C (-14°F). Travelers should be prepared for a wide range of temperatures, so dressing in layers and bringing warm clothing is essential.
In Castlewood in December, the precipitation amount is 31 mm (1.2 in) spread over 5 days.
In Castlewood in December, humidity is 84%. With an average temperature of -5°C (24°F), this humidity feels like an icy blanket wrapped around you, making the air feel even colder and more biting, which can be quite uncomfortable for traveling.
In Castlewood in December, the maximum UV index is 2, which corresponds to a low exposure category. With this level of UV radiation, the time to burn is approximately 45 minutes. To learn more about the hourly UV index in Castlewood, you can visit Hourly UV Index in Castlewood.
UV Risk Categories
Weather in Castlewood varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Castlewood, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -10°C (15°F) | 22 mm (0.9 inches) | 85% | moderate |
| February Weather | -10°C (15°F) | 18 mm (0.7 inches) | 89% | moderate |
| March Weather | -1°C (31°F) | 50 mm (2.0 inches) | 81% | high |
| April Weather | 5°C (41°F) | 68 mm (2.7 inches) | 82% | very high |
| May Weather | 13°C (56°F) | 89 mm (3.5 inches) | 76% | very high |
| June Weather | 21°C (70°F) | 79 mm (3.1 inches) | 81% | very high |
| July Weather | 23°C (73°F) | 83 mm (3.3 inches) | 82% | very high |
| August Weather | 21°C (70°F) | 109 mm (4.3 inches) | 83% | very high |
| September Weather | 17°C (63°F) | 88 mm (3.5 inches) | 82% | very high |
| October Weather | 7°C (46°F) | 77 mm (3.0 inches) | 82% | moderate |
| November Weather | 0°C (33°F) | 26 mm (1.0 inches) | 87% | moderate |
| December Weather | -5°C (24°F) | 31 mm (1.2 inches) | 84% | low |