Last updated: June 24, 2025
In Water Mill, United States, the average temperature in December hovers around 5°C (42°F). Temperatures can dip as low as -9°C (16°F) and reach as high as 16°C (61°F). Expect about 147 mm (5.8 in) of precipitation over 12 days, accompanied by an average humidity level of 80%. Stay prepared for a mix of chilly and damp days!
In December in Water Mill, the average temperature is 5°C (42°F). Maximums can reach 16°C (61°F) and minimums can drop as low as -9°C (16°F). Be prepared for a wide range of temperatures when traveling during this time.
In Water Mill in December, the precipitation amount is 147 mm (5.8 in) over a span of 12 days.
In Water Mill in December humidity is 80%. With an average temperature of 5°C (42°F), this humidity feels like a damp chill that can seep into your bones, making outdoor adventures uncomfortable and urging travelers to seek warm shelter often.
In Water Mill 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 Water Mill, you can visit Hourly UV Index in Water Mill.
UV Risk Categories
Weather in Water Mill varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Water Mill, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 2°C (37°F) | 89 mm (3.5 inches) | 84% | moderate |
| February Weather | 3°C (37°F) | 123 mm (4.8 inches) | 84% | moderate |
| March Weather | 4°C (39°F) | 113 mm (4.5 inches) | 82% | high |
| April Weather | 8°C (47°F) | 137 mm (5.4 inches) | 79% | very high |
| May Weather | 12°C (54°F) | 129 mm (5.1 inches) | 75% | very high |
| June Weather | 18°C (64°F) | 72 mm (2.9 inches) | 78% | very high |
| July Weather | 22°C (72°F) | 99 mm (3.9 inches) | 76% | very high |
| August Weather | 23°C (73°F) | 103 mm (4.0 inches) | 76% | very high |
| September Weather | 20°C (69°F) | 99 mm (3.9 inches) | 75% | very high |
| October Weather | 16°C (61°F) | 160 mm (6.3 inches) | 75% | high |
| November Weather | 10°C (50°F) | 113 mm (4.4 inches) | 80% | moderate |
| December Weather | 5°C (42°F) | 147 mm (5.8 inches) | 80% | low |