Last updated: June 24, 2025
In Mechanicsburg, United States, the average temperature in December hovers around 2°C (36°F), making it a chilly time of year. Temperatures can swing dramatically, with a minimum of -17°C (1°F) and a maximum reaching up to 18°C (65°F). Be prepared for a wet month, as you'll encounter approximately 95 mm (3.8 in) of precipitation over about 10 days. Additionally, the air can feel quite damp with an average humidity of 87%.
In December in Mechanicsburg, the average temperature is 2°C (36°F). The maximum can reach 18°C (65°F), and the minimum can be as low as -17°C (1°F). Travelers should be prepared for a wide range of temperatures and pack accordingly.
In Mechanicsburg in December, the precipitation amount is 95 mm (3.8 in) over the course of 10 days.
In Mechanicsburg in December, humidity is 87%. With an average temperature of 2°C (36°F), this humidity feels like an unwelcome chill that seeps into your bones, making outdoor exploration feel damp and heavy, and encouraging travelers to seek the warmth of indoor attractions instead.
In Mechanicsburg 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 Mechanicsburg, you can check the information here.
UV Risk Categories
Weather in Mechanicsburg varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Mechanicsburg, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -1°C (30°F) | 75 mm (3.0 inches) | 88% | moderate |
| February Weather | 1°C (34°F) | 104 mm (4.1 inches) | 88% | moderate |
| March Weather | 6°C (42°F) | 108 mm (4.2 inches) | 87% | high |
| April Weather | 11°C (52°F) | 111 mm (4.4 inches) | 85% | very high |
| May Weather | 17°C (64°F) | 131 mm (5.1 inches) | 81% | very high |
| June Weather | 22°C (72°F) | 134 mm (5.3 inches) | 82% | very high |
| July Weather | 24°C (75°F) | 120 mm (4.7 inches) | 81% | very high |
| August Weather | 23°C (73°F) | 99 mm (3.9 inches) | 73% | very high |
| September Weather | 20°C (69°F) | 94 mm (3.7 inches) | 73% | very high |
| October Weather | 14°C (58°F) | 95 mm (3.7 inches) | 78% | high |
| November Weather | 5°C (42°F) | 95 mm (3.7 inches) | 89% | moderate |
| December Weather | 2°C (36°F) | 95 mm (3.8 inches) | 87% | moderate |