Last updated: February 24, 2025
December in Guerneville, United States brings a mix of cool temperatures and significant moisture. With daily maximums reaching a pleasant 24°C (75°F) and minimums plummeting to a brisk 0°C (32°F), visitors can expect a range of weather experiences. The average temperature hovers around 9°C (49°F), setting a crisp backdrop for the season. Rainfall is characteristic, with 102 mm (4.0 in) accumulated over approximately 9 days, contributing to a relative humidity of 84% that underscores the area's lush surroundings. This month offers a cozy atmosphere ideal for exploring Guerneville’s natural beauty and vibrant community.
In Guerneville, United States, December marks a gradual transition into winter, with temperatures reflecting a cool, crisp atmosphere. The month features a minimum temperature around 0°C (32°F) and an average of 9°C (49°F), providing a chilly backdrop perfect for cozying up indoors. Daytime highs reach up to 24°C (75°F), allowing for comfortable outdoor activities on sunny days. Compared to the preceding months, December's temperatures signify a dip, yet they remain relatively mild compared to January's more frigid conditions. This trend showcases Guerneville's unique climate, where even winter months can surprise with pleasant warmth during the day, inviting exploration of the stunning natural surroundings.
In December, Guerneville experiences a notable shift in its precipitation patterns, with 102 mm (4.0 in) of rain falling over 9 days. This marks a continuation of the wetter fall season, as the town transitions from the drier summer months. The December rainfall plays a key role in replenishing local water sources, contributing significantly to the overall yearly totals, which often reach their peak in winter. Compared to the much drier months of June and July, where no precipitation is recorded, December's moisture offers a refreshing contrast, invigorating the region's landscapes just in time for the new year.
As December settles in Guerneville, the humidity rises to 84%, mirroring the levels seen in both November and February. This slight uptick hints at the region's tendency for increased moisture during the winter months, following a gradual decline from the summer's peak of 70% in July and 66% in August. Throughout the year, humidity remains relatively high, with January marking the highest level at 86%. The trend showcases a consistent pattern, where the cool, damp air of late fall and early winter contrasts sharply with the drier conditions of mid-year, creating a unique microclimate that is both refreshing and invigorating.
As the year winds down, December in Guerneville, United States, brings a return to a moderate UV Index of 3, mirroring the levels observed in January. With a burn time of 30 minutes, outdoor enthusiasts can enjoy the crisp winter air while remaining mindful of sun exposure. This seasonal shift from the extreme levels experienced in the summer months emphasizes the cyclical nature of UV radiation, peaking at a staggering 11 in June and July, before gradually tapering off. As such, December offers a gentler reminder to stay protected, making it a perfect time to savor the natural beauty of Guerneville without a high risk of sunburn. For more detailed UV index information, visit Guerneville UV Index.
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In Guerneville, December brings a gentle transition from the vibrant sunshine of summer months to the cooler embrace of winter. With 184 hours of sunshine, this month reflects a noticeable dip from the summer peaks, yet it still glimmers with charm amidst the crisp air. The trend throughout the year showcases a clear crescendo of sunlight peaking in June and July, where residents bask in 374 to 375 hours respectively. As the year draws to a close, the only other months that catch up to December's cozy luminosity are November and January, which boast 216 and 141 hours of sunlight respectively. This gradual decline in sunshine hours, though significant, allows for a unique festive atmosphere, where the beauty of Guerneville's landscapes shines even brighter against the backdrop of winter's calm.
Nestled in the picturesque landscape of Guerneville, California, December marks a notable decline in the likelihood of sunny days, with only a 36% chance of sunshine. This trend is part of a broader pattern throughout the year, where the chance of clear skies gradually increases from a modest 39% in January to a peak of 84% in May. As the seasons transition, we see the sunshine probabilities dip in the late fall, plummeting from 48% in November to their lowest point in December. While the risk of rainy days heightens during this month, the enchanting beauty of Guerneville still invites visitors to appreciate its winter charm, even when the sun isn’t shining as brightly.
As December settles in Guerneville, the daylight begins to wane, offering just 9 hours of sunlight—a noticeable dip that mirrors the shorter days of winter. This reduction in daylight is part of a gradual trend that begins in November and continues through the deepest winter months. The bright peak of summer, with its generous 14 hours of daylight from June to August, feels far away as the hours of sunshine have steadily decreased since then. As the year progresses, there’s a clear rhythm to the amount of daylight, with the months transitioning from 11 hours in October to 10 hours in November, and finally landing back at 9 hours in December. Yet, the promise of longer days is on the horizon, as Guerneville will soon embark on a journey back towards longer daylight, beginning with the arrival of January.
As the year draws to a close in Guerneville, December brings a gentle reminder of winter's presence with an average wind speed of 2.5 m/s (6 mph). This slight uptick from November's calm winds reflects a trend of gradually increasing breezes throughout the fall season. Notably, while the summer months typically see winds calm down to around 2.4 m/s (5 mph), the transition toward winter aligns with a subtle rise in wind activity. As the year progresses, May stands out as the peak month with 4.1 m/s (9 mph), showcasing the warmer season's livelier air. Overall, the winds in December maintain a cool, steady flow, inviting residents and visitors alike to embrace the tranquil charm of the season in this picturesque locale.
The weather in Guerneville 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 Guerneville and find detailed weather information for every month.
December and January weather exhibits some notable differences. While December experiences a minimum temperature of 0°C and an average of 9°C, January sees slightly cooler mornings with a minimum temperature of -1°C. Both months have similar maximum temperatures, with January peaking at 25°C compared to December's 24°C. Precipitation increases in January, reaching 140 mm over 9 days, compared to December's 102 mm, while humidity is marginally higher in January at 86% compared to December's 84%. For more detailed insights, check out Guerneville weather in January.
When comparing the weather in December and February, we see that both months experience mild temperatures, but February tends to be colder at night with minimum temperatures dipping to -3°C (27°F) compared to December's minimum of 0°C (32°F). The average temperature in February is slightly higher at 10°C (51°F), while the maximum temperature aligns closely between the two months, reaching 25°C (77°F) in February and 24°C (75°F) in December. Precipitation is more significant in February, totaling 157 mm (6.2 in) over 8 days, compared to December's 102 mm (4.0 in) over 9 days. Both months share the same humidity level of 84%, contributing to a moist atmosphere. For a detailed look at February weather, check out Guerneville weather in February.
In December, the weather tends to be cooler with average temperatures ranging from a minimum of 0°C (32°F) to a maximum of 24°C (75°F), while March sees slightly warmer conditions with averages between 0°C (32°F) and 26°C (80°F). Precipitation is quite similar in both months, with December receiving 102 mm (4.0 in) over 9 days and March totaling 96 mm (3.8 in) across 10 days. Humidity levels are comparable as well, with December at 84% and March at 83%. For a closer look at the specific conditions during this latter month, you can visit Guerneville weather in March.
December and April present contrasting weather patterns. In December, temperatures range from a chilly minimum of 0°C (32°F) to a comfortable maximum of 24°C (75°F), with an average of 9°C (49°F). The month experiences higher precipitation, with 102 mm (4.0 in) falling over 9 days, and humidity levels rise to 84%. In contrast, April offers milder conditions, starting with a minimum of 3°C (37°F) and reaching a warmer maximum of 30°C (86°F), averaging 13°C (57°F). Precipitation is significantly lower at 47 mm (1.9 in) across 6 days, and humidity decreases slightly to 80%. For more details on the April weather, check out Guerneville weather in April.
In December, temperatures range from a chilly 0°C (32°F) at night to a mild 24°C (75°F) during the day, with an average of 9°C (49°F). The month experiences significant precipitation, totaling 102 mm (4.0 in) over approximately 9 wet days, contributing to a high humidity of 84%. In contrast, May brings warmer temperatures, with a minimum of 5°C (41°F) and a maximum that can reach up to 33°C (91°F), averaging 16°C (60°F). Rainfall is scarce in May, accumulating only 30 mm (1.2 in) across about 3 days, and the humidity is slightly lower at 80%. For more details about the weather in May, check out Guerneville weather in May.
December and June present stark contrasts in weather conditions. In December, temperatures range from a chilly minimum of 0°C (32°F) to a more comfortable maximum of 24°C (75°F), with an average temperature of 9°C (49°F). This month also experiences considerable precipitation, averaging 102 mm (4.0 in) over about 9 days, and high humidity levels of 84%. In contrast, June boasts milder weather with minimum temperatures of 9°C (48°F) and a much warmer maximum of 37°C (99°F), resulting in an average of 19°C (67°F). Remarkably, June sees minimal rainfall, recording only 2 mm (0.1 in) across no precipitation days, along with lower humidity at 76%. For more details about June weather, you can check out Guerneville weather in June.
December and July reveal stark contrasts in weather patterns. December experiences cooler temperatures, with a minimum of 0°C (32°F) and an average of 9°C (49°F), peaking at 24°C (75°F). This month also sees notable precipitation, with an average of 102 mm (4.0 in) spread over 9 rainy days, contributing to a higher humidity level of 84%. In contrast, July boasts much warmer conditions, with temperatures ranging from a minimum of 11°C (53°F) to a maximum of 35°C (95°F) and a comfortable average of 20°C (68°F). Remarkably, July experiences no rainfall, leading to a dry climate with a lower humidity of 70%. For more detailed insights, you can check the Guerneville weather in July.
When comparing the weather in December and August, it's clear that they offer vastly different experiences. December features cooler temperatures, with a minimum of 0°C (32°F) and an average of 9°C (49°F), peaking at a mild 24°C (75°F), along with significant precipitation of 102 mm (4.0 in) over 9 days, resulting in a high humidity level of 84%. In stark contrast, August enjoys much warmer conditions, with minimum temperatures of 10°C (50°F) and highs reaching 35°C (96°F), while remaining dry with no recorded precipitation, and a lower humidity of 66%. For a detailed view of what to expect during this warmer month, check out Guerneville weather in August.
December weather is characterized by cooler temperatures, with a minimum of 0°C (32°F) and an average of 9°C (49°F), while September enjoys milder conditions, ranging from a minimum of 8°C (47°F) to an average of 19°C (67°F). The maximum temperature in September can soar to 40°C (103°F), which is significantly higher than December's maximum of 24°C (75°F). Rainfall is notably more prevalent in December, with 102 mm (4.0 in) over 9 days, compared to September, which typically sees almost no precipitation at just 2 mm (0.1 in) and 0 days of rain. Additionally, December has a higher humidity level at 84%, as opposed to September's lower humidity at 68%. For more detailed insights, you can check Guerneville weather in September.
When comparing the weather in December and October, we see notable differences in temperature and precipitation. In December, the temperatures range from a minimum of 0°C (32°F) to a maximum of 24°C (75°F), with an average of 9°C (49°F). In contrast, October boasts warmer weather, with temperatures ranging from a minimum of 3°C (38°F) to a maximum of 35°C (94°F), and an average of 16°C (62°F). October also experiences significantly less precipitation, with only 43 mm (1.7 in) over just 2 days, while December is much wetter, receiving 102 mm (4.0 in) over 9 days. Additionally, December has higher humidity at 84%, compared to October's 72%. For a detailed overview of October weather, you can explore Guerneville weather in October.
In comparing the weather of December and November, December tends to be slightly cooler, with average temperatures ranging from a minimum of 0°C (32°F) to a maximum of 24°C (75°F), while November sees a broader temperature range, with a minimum of -1°C (30°F) and a maximum of 27°C (81°F). Precipitation is more prevalent in December, accumulating to 102 mm (4.0 in) over 9 days, compared to November's 61 mm (2.4 in) over just 5 days. Interestingly, both months share the same humidity level of 84%, indicating a similarly moist atmosphere during this period. For more insights into November weather patterns, you can visit Guerneville weather in November.
As December arrives in Guerneville, the weather takes on a distinct character compared to other months. With a notable increase in precipitation, accompanied by higher humidity levels, this time of year brings a refreshing chill to the air, contrasting sharply with the warmer temperatures experienced in the summer. While you can still expect mild highs, the cooler averages and occasional frosty mornings remind us that winter is here. The added rain creates a lush backdrop, transforming the landscape and offering a unique charm that sets December apart. For those curious about the overall climate trends in Guerneville, additional insights can be found at Guerneville Climate.