Last updated: June 24, 2025
In December, the average temperature in Mattawa, United States hovers around 0°C (33°F), with a minimum chill of -12°C (11°F) and an occasional warm peak at 18°C (64°F). Expect around 38 mm (1.5 in) of precipitation across 9 days, and stay prepared for a high average humidity of 88%, making it feel quite brisk!
In December in Mattawa, the average temperature is 0°C (33°F). Maximums can reach 18°C (64°F), while minimums can dip as low as -12°C (11°F). This weather makes it essential for travelers to be prepared for cold conditions, with warm clothing and layers being a must.
In Mattawa in December, the total precipitation amount is 38 mm (1.5 in) spread over a duration of 9 days.
In Mattawa in December, humidity is 88%. With an average temperature of 0°C (33°F), this humidity feels like a damp chill that seeps into your bones, making travel uncomfortable and requiring extra layers to stay warm and dry.
In Mattawa 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 Mattawa, you can visit Hourly UV Index in Mattawa.
UV Risk Categories
Weather in Mattawa varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Mattawa, focusing on differences in temperature, rainfall, humidity, and UV levels.
Temperature | Precipitation | Humidity | UV | |
---|---|---|---|---|
January Weather | -1°C (31°F) | 45 mm (1.8 inches) | 86% | low |
February Weather | 0°C (33°F) | 43 mm (1.7 inches) | 86% | moderate |
March Weather | 6°C (43°F) | 27 mm (1.1 inches) | 87% | moderate |
April Weather | 11°C (52°F) | 26 mm (1.0 inches) | 84% | high |
May Weather | 17°C (63°F) | 17 mm (0.7 inches) | 81% | very high |
June Weather | 21°C (70°F) | 7 mm (0.3 inches) | 82% | very high |
July Weather | 25°C (77°F) | 1 mm (0.0 inches) | 79% | very high |
August Weather | 25°C (77°F) | 5 mm (0.2 inches) | 63% | very high |
September Weather | 19°C (66°F) | 14 mm (0.5 inches) | 62% | high |
October Weather | 11°C (51°F) | 33 mm (1.3 inches) | 83% | moderate |
November Weather | 4°C (40°F) | 35 mm (1.4 inches) | 89% | moderate |
December Weather | 0°C (33°F) | 38 mm (1.5 inches) | 88% | low |