Last updated: June 24, 2025
In Mason, United States, the average temperature in December hovers around 8°C (46°F). Temperatures can swing from a chilly -10°C (14°F) at their lowest to a comfortable 24°C (76°F) at their peak. Expect about 145 mm (5.7 in) of precipitation over 10 days, while the average humidity rests at a muggy 88%. Be prepared for a mix of weather as you explore this unique destination!
In December in Mason, the average temperature is 8°C (46°F), with maximums reaching 24°C (76°F) and minimums dropping as low as -10°C (14°F). This range provides an opportunity for travelers to experience a diverse climate, so be sure to pack accordingly for both warm and cold activities.
In Mason in December, the precipitation amount is 145 mm (5.7 in) spread over a duration of 10 days.
In Mason in December, humidity is 88%. With an average temperature of 8°C (46°F), this humidity feels like a damp chill that seeps into your bones, making outdoor exploration feel much more uncomfortable than the temperature alone would suggest.
In Mason 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 Mason, you can check the information here.
UV Risk Categories
Weather in Mason varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Mason, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 5°C (42°F) | 102 mm (4.0 inches) | 86% | moderate |
| February Weather | 7°C (45°F) | 172 mm (6.8 inches) | 85% | high |
| March Weather | 12°C (55°F) | 169 mm (6.6 inches) | 84% | high |
| April Weather | 16°C (61°F) | 139 mm (5.5 inches) | 81% | very high |
| May Weather | 22°C (72°F) | 108 mm (4.2 inches) | 83% | very high |
| June Weather | 26°C (78°F) | 106 mm (4.2 inches) | 83% | extreme |
| July Weather | 27°C (82°F) | 120 mm (4.7 inches) | 80% | extreme |
| August Weather | 26°C (79°F) | 113 mm (4.5 inches) | 73% | very high |
| September Weather | 24°C (76°F) | 102 mm (4.0 inches) | 70% | very high |
| October Weather | 18°C (64°F) | 114 mm (4.5 inches) | 73% | high |
| November Weather | 10°C (50°F) | 80 mm (3.1 inches) | 85% | moderate |
| December Weather | 8°C (46°F) | 145 mm (5.7 inches) | 88% | moderate |