Last updated: June 24, 2025
In December, the average temperature in Grantsville, United States hovers around 4°C (40°F). This month can bring a chill with minimum temperatures dropping to -14°C (7°F), while it can rise to a pleasant 20°C (69°F) at times. Expect about 122 mm (4.8 in) of precipitation spread over 12 days, contributing to an average humidity level of 86%. Be prepared for a mix of weather as you explore this captivating destination!
In December in Grantsville, the average temperature is 4°C (40°F). Maximums can reach 20°C (69°F), while minimums can drop as low as -14°C (7°F). Be sure to pack layers to stay comfortable during your travels!
In Grantsville in December, the precipitation amount is 122 mm (4.8 in) over a span of 12 days.
In Grantsville in December humidity is 86%. With an average temperature of 4°C (40°F), this humidity feels like a damp chill that seeps into your bones, making outdoor activities uncomfortable and travel cumbersome as you navigate through a thick, heavy air that clings to your skin.
In Grantsville 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 Grantsville, you can check the information here.
UV Risk Categories
Weather in Grantsville varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Grantsville, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 2°C (35°F) | 98 mm (3.9 inches) | 88% | moderate |
| February Weather | 4°C (40°F) | 142 mm (5.6 inches) | 88% | moderate |
| March Weather | 8°C (46°F) | 115 mm (4.5 inches) | 88% | high |
| April Weather | 13°C (55°F) | 142 mm (5.6 inches) | 86% | very high |
| May Weather | 18°C (65°F) | 160 mm (6.3 inches) | 82% | very high |
| June Weather | 22°C (72°F) | 172 mm (6.8 inches) | 84% | very high |
| July Weather | 24°C (76°F) | 129 mm (5.1 inches) | 82% | very high |
| August Weather | 23°C (74°F) | 120 mm (4.7 inches) | 73% | very high |
| September Weather | 21°C (70°F) | 106 mm (4.2 inches) | 73% | very high |
| October Weather | 15°C (60°F) | 116 mm (4.6 inches) | 81% | high |
| November Weather | 7°C (45°F) | 81 mm (3.2 inches) | 89% | moderate |
| December Weather | 4°C (40°F) | 122 mm (4.8 inches) | 86% | moderate |