Last updated: February 24, 2025
In Sonoma, United States, December brings a diverse weather experience characterized by a maximum temperature of 23°C (73°F) and an average of 10°C (50°F), offering a crisp yet pleasant winter climate. The season's chill is underscored by a minimum temperature dipping to 0°C (33°F), creating the perfect backdrop for cozy gatherings. December also sees 94 mm (3.7 in) of rain spread over approximately 9 days, contributing to the region's lush landscape. With humidity levels at a comfortable 84%, Sonoma welcomes visitors to revel in its serene winter beauty while enjoying various seasonal activities and local offerings.
In December, Sonoma's temperatures begin to cool down, reflecting the transition into winter. With minimums hovering around 0°C (33°F) and a comfortable average of 10°C (50°F), the weather remains mild compared to the cold snaps seen in other parts of the world. Daytime highs reach up to 23°C (73°F), offering a gentle reminder of the region's temperate climate, even as the year draws to a close. This month sets the stage for the cooler months ahead while maintaining a pleasantly moderate temperature range that invites both local and visiting wine enthusiasts to enjoy the serene beauty of Sonoma's winter landscapes.
December in Sonoma brings a notable uptick in precipitation as the year winds down, with 94 mm (3.7 in) of rainfall over approximately 9 days. This marks an increase from the drier months preceding it, as both October and November experienced less rainfall—33 mm (1.3 in) and 50 mm (2.0 in) respectively, over fewer days. The consistent rain in December sets the stage for the wet season, showcasing a trend where the latter part of the year sees significantly more moisture. As winter approaches, Sonoma's landscape transforms, highlighting the importance of this month's rainfall in replenishing local ecosystems and preparing for the lush growth of the upcoming months.
December in Sonoma marks a return to elevated humidity levels, with a comfortable 84% that mirrors the humidity of November. This peak in moisture showcases a trend where the latter part of the year sees a gradual rise, contrasting with the drier summer months, particularly July and August when humidity dips to 70% and 66% respectively. As we transition from the dryness of summer into the wetter winter season, the overall pattern reveals a notable oscillation—from the highs of 86% in January to the lows of 66% in August—creating a dynamic climate that balances the crispness of winter with the lingering warmth of late autumn. This cyclical variation not only affects the local environment but also beautifully illustrates Sonoma's diverse seasonal charm.
In December, Sonoma's UV Index returns to a moderate level of 3, providing a brief respite from the peak exposure months. This trend reflects a gradual decline from the summer's extreme conditions, where values reached up to 11 in both June and July, requiring only 10 minutes for potential skin damage. As autumn set in, the UV levels began to taper off, dropping to 4 in November, and now maintain a more manageable 30-minute burn time in December. This seasonal transition highlights the importance of mindful sun protection, even in the cooler months. For further insights on seasonal UV levels, check out the Sonoma UV Index.
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December in Sonoma offers a delightful balance of sunlight, with 185 hours illuminating the month. While this is a notable decrease from the peak summer month of July, which sees an impressive 394 hours, it still reflects a charming winter setting. Notably, as the year winds down, the sun hours dip gradually from the vibrant heights of spring and summer—March's 257 hours and May's 357 hours mark the transition into longer nights. December's light, though less intense than the preceding months, allows for cozy holiday gatherings under the soft, warm glow of the sun, creating an inviting atmosphere that embodies the essence of this beautiful region.
In Sonoma, the likelihood of enjoying sunny weather in December stands at a modest 32%, marking a significant dip as the year winds down. This decline in sunshine is part of a broader trend, with the chance of sunny days steadily increasing from 39% in January to a peak of 82% in May. After reaching its high, the probability of clear skies begins to wane, dropping notably in the later months. With December’s cloudy tendencies, travelers and locals alike may want to prepare for cooler, overcast days as the festive season approaches, contrasting sharply with the vibrant sunshine characteristic of the spring and summer months.
As December rolls into Sonoma, daylight hours dip to 9 hours, mirroring the earlier months of January and November. This seasonal decline signals the transition to winter, as days grow shorter and nights longer. Interestingly, from March onwards, there's a noticeable upward trend, with daylight peaking at 14 hours during the summer months of May, June, and July. Following this peak, daylight gradually decreases, offering a rhythmic return to the crisp, cozy days of winter. The cyclic nature of daylight duration not only marks the changing seasons but also invites residents and visitors alike to embrace the unique charm of Sonoma during the festive, shorter days of December.
In Sonoma, December brings a gentle breeze with an average wind speed of 2.2 m/s (5 mph), reflecting a slight increase from the calmer November winds. Throughout the year, wind speeds in Sonoma show a gradual rise from the tranquility of winter months to the more spirited gusts of late spring and early summer, peaking at 3.2 m/s (7 mph) in May. As summer wanes into the cooler, crispness of autumn, winds begin to calm once more, signaling a return to the serene atmosphere of winter. Overall, December's winds maintain the area's characteristic softness, creating a pleasant backdrop for the festive season in this picturesque region.
The weather in Sonoma changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of December's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Sonoma and find detailed weather information for every month.
In December, temperatures in Sonoma typically range from a minimum of 0°C (33°F) to a maximum of 23°C (73°F), with an average temperature of 10°C (50°F). The month sees about 94 mm (3.7 in) of precipitation over 9 days, accompanied by humidity levels around 84%. In contrast, January experiences slightly cooler temperatures, with a minimum of -1°C (31°F) and a maximum of 24°C (76°F), while still maintaining the same average of 10°C (50°F). January also brings more precipitation, totaling 125 mm (4.9 in) over the same number of rainy days, leading to a slight increase in humidity to 86%. For detailed weather information specific to January, you can visit Sonoma weather in January.
In December, the weather typically sees a minimum temperature of 0°C (33°F), with an average of 10°C (50°F) and a maximum of 23°C (73°F). It experiences 94 mm (3.7 in) of precipitation over about 9 days, maintaining a humidity level of 84%. Conversely, February has a slightly cooler minimum temperature of -1°C (30°F), with an average of 11°C (52°F) and a higher maximum of 26°C (79°F). This month brings more precipitation at 127 mm (5.0 in) over 8 days, while humidity remains the same at 84%. For a more in-depth look at February’s weather specifics, you can visit Sonoma weather in February.
In December, temperatures range from a minimum of 0°C (33°F) to a maximum of 23°C (73°F), with an average of 10°C (50°F). This month experiences about 94 mm (3.7 in) of precipitation over approximately 9 days, accompanied by a high humidity level of 84%. In contrast, March brings slightly warmer conditions, with temperatures ranging from a minimum of 1°C (34°F) to a maximum of 27°C (80°F), averaging 12°C (54°F). Precipitation in March totals around 84 mm (3.3 in) spread over 10 days, while humidity remains comparable at 83%. For a closer look at weather patterns specifically in March, visit Sonoma weather in March.
In December, temperatures range from a chilly 0°C (33°F) at night to a mild maximum of 23°C (73°F) during the day, with an average around 10°C (50°F). The month is relatively wet, accumulating 94 mm (3.7 in) of precipitation over about 9 days and maintaining a high humidity level of 84%. In contrast, April brings warmer weather, with temperatures starting at 3°C (38°F) and peaking at 30°C (86°F), averaging 14°C (58°F). Precipitation drops significantly to 36 mm (1.4 in) spread over just 5 days, and humidity decreases slightly to 80%. For more detailed information, you can check Sonoma weather in April.
December and May exhibit striking differences in weather patterns. In December, temperatures range from a chilly minimum of 0°C (33°F) to a mild maximum of 23°C (73°F), with an average of 10°C (50°F). The month also experiences considerable precipitation, totaling 94 mm (3.7 in) over about 9 days, and humidity levels are quite high at 84%. In contrast, May starts with warmer temperatures, with a minimum of 5°C (41°F) and soaring to a maximum of 34°C (93°F), averaging 17°C (62°F). Precipitation drops significantly to just 21 mm (0.8 in) over a mere 3 days, and humidity levels are slightly lower at 80%. For more details on the weather in May, you can check Sonoma weather in May.
The weather in December presents a stark contrast to that of June. In December, temperatures range from a chilly minimum of 0°C (33°F) to a mild maximum of 23°C (73°F), with an average around 10°C (50°F). This month also sees significant precipitation, with 94 mm (3.7 in) falling over about 9 days, accompanied by high humidity levels at 84%. In comparison, June experiences much warmer temperatures, with a minimum of 10°C (50°F) rising to a scorching maximum of 37°C (99°F) and an average of 20°C (68°F). Remarkably, June boasts almost perfect weather, recording just 1 mm (0.1 in) of precipitation across no rainy days and a lower humidity of 76%. For more details on the delightful weather conditions during this month, check out Sonoma weather in June.
December and July present stark contrasts in weather patterns. In December, temperatures range from a chilly minimum of 0°C (33°F) to a pleasant maximum of 23°C (73°F), with an average temperature settling around 10°C (50°F). The month experiences significant precipitation, totaling 94 mm (3.7 in) across about 9 days, alongside a high humidity of 84%. In contrast, July boasts much warmer conditions, with minimum temperatures starting at 11°C (53°F) and peaking at a sweltering 36°C (96°F), giving an average of 20°C (68°F). Notably, July is remarkably dry, receiving no precipitation throughout the month, and maintaining a lower humidity level of 70%. For a closer look at the summer climate, check out Sonoma weather in July.
December and August present strikingly different weather patterns. In December, temperatures range from a chilly minimum of 0°C (33°F) to a mild maximum of 23°C (73°F), with an average of 10°C (50°F). This month also experiences significant precipitation of 94 mm (3.7 in) over about 9 days, accompanied by a high humidity level of 84%. In contrast, August boasts much warmer temperatures, with a minimum of 11°C (52°F) and a maximum soaring to 36°C (98°F), averaging around 20°C (68°F). Remarkably, August sees no precipitation, maintaining dry conditions with humidity at a comfortable 66%. For more details, check out Sonoma weather in August.
In comparing the weather in December and September, December experiences much cooler temperatures, with a minimum of 0°C (33°F) and an average of 10°C (50°F), while September boasts warmer temperatures, with a minimum of 9°C (48°F) and an average of 20°C (68°F). Additionally, December is characterized by significantly higher precipitation, with 94 mm (3.7 in) and 9 rainy days, in stark contrast to September, which typically sees minimal rainfall with just 1 mm (0.0 in) across 0 rainy days. Humidity levels are also higher in December at 84%, compared to September's 68%. For a more detailed look at September weather, you can check Sonoma weather in September.
When comparing the weather in December to October, it's clear that each month has its distinct characteristics. In December, temperatures range from a minimum of 0°C (33°F) to a maximum of 23°C (73°F), with an average of 10°C (50°F). This month experiences significantly more precipitation, with 94 mm (3.7 in) over approximately 9 days and a higher humidity level of 84%. In contrast, October boasts milder temperatures, starting at a minimum of 4°C (40°F) and peaking at 34°C (94°F), with an impressive average of 17°C (63°F). The month sees much less rain, only 33 mm (1.3 in) over just 2 days, accompanied by a lower humidity of 72%. For a closer look at October's pleasant weather, check out Sonoma weather in October.
In comparing the weather between November and December, December experiences a slightly colder range, with minimum temperatures dropping to 0°C (33°F) compared to November's 1°C (34°F). The average temperature in December is also marginally lower at 10°C (50°F), while November holds a mild average of 12°C (55°F). Additionally, December sees increased precipitation of 94 mm (3.7 in) over 9 days, nearly doubling November's 50 mm (2.0 in) across just 5 days. Despite these differences, both months maintain a consistent humidity level of 84%. For a more detailed overview of November's weather, you can visit Sonoma weather in November.
As December unfolds in Sonoma, the weather takes on a distinctly chilly character, marking a departure from the mild temperatures of preceding months. With an average of 10°C (50°F), the days are cooler, and nighttime can bring temperatures as low as 0°C (33°F). This month also experiences a noticeable increase in precipitation, averaging 94 mm (3.7 in) over about nine days, creating a damp and refreshing atmosphere that contrasts with the dry heat of summer. Additionally, the humidity rises to an average of 84%, contributing to a cozy, wintry vibe that invites locals and visitors alike to embrace seasonal activities. For a deeper understanding of Sonoma's climate patterns, explore our comprehensive guide on Sonoma Climate.