Last updated: June 24, 2025
In December, the average temperature in Norwalk, United States hovers around 2°C (35°F). Expect to experience a range from a chilly -18°C (0°F) at the lowest to a mild 16°C (61°F) at the highest. This month brings 87 mm (3.4 in) of precipitation over 12 days, contributing to an average humidity of 86%. Be prepared for a cool and damp atmosphere!
In December in Norwalk, the average temperature is 2°C (35°F), with maximums reaching up to 16°C (61°F) and minimums dropping as low as -18°C (0°F). Travelers should be prepared for cold weather and significant temperature fluctuations during this time.
In Norwalk in December, the precipitation amount is 87 mm (3.4 in) over the course of 12 days.
In Norwalk in December humidity is 86%. With an average temperature of 2°C (35°F), this humidity feels like a damp chill that seeps into your bones, making traveling quite uncomfortable as your clothes cling to you and the cold air cuts through any warmth you try to find.
In Norwalk 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 Norwalk, you can visit Hourly UV Index in Norwalk.
UV Risk Categories
Weather in Norwalk varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Norwalk, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -1°C (30°F) | 83 mm (3.3 inches) | 88% | moderate |
| February Weather | 0°C (32°F) | 95 mm (3.7 inches) | 87% | moderate |
| March Weather | 4°C (39°F) | 99 mm (3.9 inches) | 87% | high |
| April Weather | 9°C (49°F) | 120 mm (4.7 inches) | 87% | very high |
| May Weather | 16°C (61°F) | 129 mm (5.1 inches) | 81% | very high |
| June Weather | 21°C (70°F) | 124 mm (4.9 inches) | 82% | very high |
| July Weather | 24°C (75°F) | 124 mm (4.9 inches) | 81% | very high |
| August Weather | 23°C (73°F) | 86 mm (3.4 inches) | 78% | very high |
| September Weather | 20°C (68°F) | 81 mm (3.2 inches) | 78% | very high |
| October Weather | 14°C (58°F) | 105 mm (4.2 inches) | 82% | high |
| November Weather | 5°C (42°F) | 99 mm (3.9 inches) | 89% | moderate |
| December Weather | 2°C (35°F) | 87 mm (3.4 inches) | 86% | low |