Last updated: June 24, 2025
In December, the average temperature in Sedro-Woolley, United States hovers around 3°C (38°F), with minimum lows plunging to -14°C (8°F) and highs reaching up to 12°C (54°F). Expect 271 mm (10.7 in) of precipitation over approximately 19 days, and prepare for a damp experience with an average humidity level of 89%.
In December in Sedro-Woolley, the average temperature is 3°C (38°F), with maximums reaching up to 12°C (54°F) and minimums dropping as low as -14°C (8°F). It's advisable for travelers to pack warm clothing and be prepared for chilly conditions during this time.
In Sedro-Woolley in December, the precipitation amount is 271 mm (10.7 in) over the course of 19 days.
In Sedro-Woolley in December, humidity is 89%. With an average temperature of 3°C (38°F), this humidity feels like a chilly blanket wrapping around you, making travel uncomfortable as the dampness seeps into your clothes and lingers in the air, leaving you feeling cold and clammy.
In Sedro-Woolley 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 Sedro-Woolley, you can visit Hourly UV Index in Sedro-Woolley.
UV Risk Categories
Weather in Sedro-Woolley varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Sedro-Woolley, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 3°C (38°F) | 236 mm (9.3 inches) | 87% | low |
| February Weather | 2°C (36°F) | 244 mm (9.6 inches) | 86% | moderate |
| March Weather | 5°C (42°F) | 191 mm (7.5 inches) | 88% | moderate |
| April Weather | 8°C (47°F) | 146 mm (5.8 inches) | 86% | high |
| May Weather | 12°C (54°F) | 82 mm (3.2 inches) | 82% | very high |
| June Weather | 15°C (59°F) | 75 mm (3.0 inches) | 82% | very high |
| July Weather | 17°C (63°F) | 31 mm (1.2 inches) | 85% | very high |
| August Weather | 18°C (64°F) | 26 mm (1.0 inches) | 77% | very high |
| September Weather | 15°C (59°F) | 146 mm (5.8 inches) | 76% | high |
| October Weather | 9°C (49°F) | 229 mm (9.0 inches) | 88% | moderate |
| November Weather | 6°C (43°F) | 312 mm (12.3 inches) | 88% | low |
| December Weather | 3°C (38°F) | 271 mm (10.7 inches) | 89% | low |