Last updated: June 24, 2025
In December, the average temperature in Glen Lyon, United States hovers around 1°C (34°F), with extremes that can dip to a chilly -17°C (2°F) or rise as high as 16°C (61°F). Expect about 83 mm (3.3 in) of precipitation, spread over 12 days, making for a rather wet month. Additionally, the air is quite humid, with an average humidity level of 85%, enhancing that crisp, cool feel.
In December, in Glen Lyon, the average temperature is 1°C (34°F). Maximum temperatures can reach 16°C (61°F) while minimums can drop to as low as -17°C (2°F). Be prepared for extreme temperature fluctuations if you plan to travel during this time.
In Glen Lyon in December, the precipitation amount is 83 mm (3.3 in) distributed over the course of 12 days.
In Glen Lyon in December, humidity is 85%. With an average temperature of 1°C (34°F), this humidity feels like a biting chill that seeps into your bones, making outdoor travel uncomfortable and urging you to seek warmth indoors rather than explore the surroundings.
In Glen Lyon 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 Glen Lyon, you can visit Hourly UV Index in Glen Lyon.
UV Risk Categories
Weather in Glen Lyon varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Glen Lyon, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -2°C (29°F) | 71 mm (2.8 inches) | 87% | moderate |
| February Weather | 0°C (32°F) | 96 mm (3.8 inches) | 85% | moderate |
| March Weather | 3°C (38°F) | 88 mm (3.5 inches) | 85% | high |
| April Weather | 9°C (49°F) | 102 mm (4.0 inches) | 83% | very high |
| May Weather | 15°C (60°F) | 122 mm (4.8 inches) | 75% | very high |
| June Weather | 20°C (68°F) | 95 mm (3.7 inches) | 73% | very high |
| July Weather | 23°C (74°F) | 118 mm (4.6 inches) | 65% | very high |
| August Weather | 22°C (72°F) | 121 mm (4.8 inches) | 62% | very high |
| September Weather | 18°C (65°F) | 102 mm (4.0 inches) | 66% | very high |
| October Weather | 13°C (55°F) | 114 mm (4.5 inches) | 79% | high |
| November Weather | 5°C (41°F) | 87 mm (3.4 inches) | 87% | moderate |
| December Weather | 1°C (34°F) | 83 mm (3.3 inches) | 85% | low |