Last updated: June 24, 2025
In Lisbon, United States, the average temperature in December hovers around -4°C (24°F). Expect to navigate a wide temperature range, with minimums dropping to -29°C (-21°F) and maximums reaching a balmy 15°C (58°F). During this time, you can anticipate about 84 mm (3.3 in) of precipitation spread over 13 days, accompanied by a high average humidity of 85%. Embrace the chill!
In December in Lisbon, the average temperature is -4°C (24°F). Maximum temperatures can reach up to 15°C (58°F), while minimums can drop as low as -29°C (-21°F). Travelers should be prepared for a wide range of temperatures and pack accordingly for both chilly and milder conditions.
In Lisbon in December, the precipitation amount is 84 mm (3.3 in) during 13 days, indicating a relatively wet period for that time of year.
In Lisbon in December, humidity is 85%. With an average temperature of -4°C (24°F), this humidity feels like a biting chill that penetrates your layers, making outdoor exploration uncomfortable and urging you to seek warm shelter frequently.
In Lisbon 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 Lisbon, you can visit Hourly UV Index in Lisbon.
UV Risk Categories
Weather in Lisbon varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Lisbon, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -7°C (19°F) | 76 mm (3.0 inches) | 91% | low |
| February Weather | -5°C (22°F) | 75 mm (3.0 inches) | 89% | moderate |
| March Weather | -1°C (30°F) | 65 mm (2.6 inches) | 85% | moderate |
| April Weather | 6°C (43°F) | 109 mm (4.3 inches) | 84% | very high |
| May Weather | 13°C (55°F) | 92 mm (3.6 inches) | 78% | very high |
| June Weather | 18°C (64°F) | 95 mm (3.7 inches) | 72% | very high |
| July Weather | 21°C (69°F) | 110 mm (4.3 inches) | 75% | very high |
| August Weather | 20°C (67°F) | 79 mm (3.1 inches) | 74% | very high |
| September Weather | 16°C (60°F) | 63 mm (2.5 inches) | 77% | high |
| October Weather | 9°C (49°F) | 129 mm (5.1 inches) | 85% | moderate |
| November Weather | 1°C (34°F) | 100 mm (3.9 inches) | 86% | moderate |
| December Weather | -4°C (24°F) | 84 mm (3.3 inches) | 85% | low |