Last updated: August 23, 2025
In December, the average temperature in St Martin, Guernsey hovers around 11°C (51°F), with daily fluctuations ranging from a chilly 5°C (41°F) to a mild 14°C (58°F). Be prepared for wet weather, as precipitation averages 163 mm (6.4 in) spread over 21 days, contributing to a high humidity level of 90%. Don't forget your umbrella!
In December in St Martin, the average temperature is 11°C (51°F). The maximum can reach 14°C (58°F), while the minimum can be as low as 5°C (41°F). It's a mild time to visit, making it ideal for outdoor activities and exploring the area comfortably.
In St Martin in December, the precipitation amount is 163 mm (6.4 in), occurring over the course of 21 days.
In St Martin in December, humidity is 90%. With an average temperature of 11°C (51°F), this humidity feels like a damp blanket wrapping around you, making traveling uncomfortable and sticky, as every step leaves you feeling sluggish and clinging to the air.
In St Martin in December, the maximum UV index is 1, which corresponds to a low Exposure Category. This means you have a time to burn of 45 minutes. For more details, you can check the Hourly UV Index in St Martin.
UV Risk Categories
Weather in St Martin varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in St Martin, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 9°C (49°F) | 94 mm (3.7 inches) | 89% | low |
| February Weather | 9°C (48°F) | 86 mm (3.4 inches) | 88% | moderate |
| March Weather | 9°C (49°F) | 73 mm (2.9 inches) | 85% | moderate |
| April Weather | 10°C (50°F) | 34 mm (1.3 inches) | 84% | high |
| May Weather | 12°C (54°F) | 55 mm (2.2 inches) | 81% | high |
| June Weather | 14°C (58°F) | 59 mm (2.3 inches) | 77% | very high |
| July Weather | 16°C (62°F) | 37 mm (1.5 inches) | 63% | very high |
| August Weather | 17°C (63°F) | 50 mm (2.0 inches) | 71% | high |
| September Weather | 17°C (62°F) | 63 mm (2.5 inches) | 76% | high |
| October Weather | 15°C (59°F) | 144 mm (5.7 inches) | 89% | moderate |
| November Weather | 12°C (54°F) | 126 mm (5.0 inches) | 90% | low |
| December Weather | 11°C (51°F) | 163 mm (6.4 inches) | 90% | low |