Last updated: June 24, 2025
In December, the average temperature in Johnson City, United States is a mild 12°C (54°F), with remarkable variations ranging from a chilly -4°C (26°F) to a warm 28°C (82°F). Expect a moderate level of precipitation, with about 46 mm (1.8 in) falling over 5 days, contributing to an average humidity of 87%. Be prepared for a potentially wet and humid climate!
In December in Johnson City, the average temperature is 12°C (54°F). The maximum can reach 28°C (82°F), and the minimum can be as low as -4°C (26°F). This makes it a great time for travelers to experience a diverse range of weather, so pack accordingly for both warm days and chilly nights.
In Johnson City in December, the precipitation amount is 46 mm (1.8 in) recorded over a span of 5 days.
In Johnson City in December humidity is 87%. With an average temperature of 12°C (54°F), this humidity feels like a damp embrace, making it quite uncomfortable for traveling, as the air feels heavy and can quickly sap your energy as you explore the sights.
In Johnson City in December, the maximum UV index reaches 5, which corresponds to a moderate Exposure Category. Under these conditions, the estimated time to burn is approximately 30 minutes. For more details, you can check the Hourly UV Index in Johnson City.
UV Risk Categories
Weather in Johnson City varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Johnson City, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 10°C (50°F) | 46 mm (1.8 inches) | 78% | moderate |
| February Weather | 11°C (52°F) | 62 mm (2.4 inches) | 78% | high |
| March Weather | 17°C (62°F) | 65 mm (2.6 inches) | 77% | very high |
| April Weather | 20°C (67°F) | 71 mm (2.8 inches) | 78% | extreme |
| May Weather | 24°C (75°F) | 140 mm (5.5 inches) | 82% | extreme |
| June Weather | 27°C (81°F) | 73 mm (2.9 inches) | 78% | extreme |
| July Weather | 29°C (84°F) | 57 mm (2.2 inches) | 69% | extreme |
| August Weather | 29°C (84°F) | 81 mm (3.2 inches) | 63% | extreme |
| September Weather | 26°C (78°F) | 99 mm (3.9 inches) | 66% | extreme |
| October Weather | 20°C (69°F) | 95 mm (3.7 inches) | 73% | very high |
| November Weather | 15°C (59°F) | 33 mm (1.3 inches) | 84% | high |
| December Weather | 12°C (54°F) | 46 mm (1.8 inches) | 87% | moderate |