Last updated: February 24, 2025
January in Sonoma, United States presents a blend of brisk winter temperatures and notable moisture, making it a unique time of year. The maximum temperature reaches an inviting 24°C (76°F) while the average hovers around a cool 10°C (50°F), dipping to a chilly minimum of -1°C (31°F). With precipitation accumulating to 125 mm (4.9 in) over approximately 9 days, residents and visitors can expect frequent rainfall, contributing to the region's lush landscapes. Humidity levels are relatively high at 86%, enhancing the crispness of the air. This combination of mild warmth and wet conditions shapes January as a reflective month in Sonoma, ideal for cozy indoor activities or exploring the region's natural beauty.
In Sonoma, United States, January ushers in the year with a varied temperature range, starting with a minimum of -1°C (31°F) and peaking at a maximum of 24°C (76°F). The average temperature settles around 10°C (50°F), providing a mild yet brisk winter experience. This month marks the transition toward gradually warming days, as February builds on January’s cool foundations with slightly higher average temperatures of 11°C (52°F). As spring approaches in March, temperatures continue to rise, hinting at the allure of warmer months ahead with highs reaching 27°C (80°F). Overall, January serves as a pivotal month, reflecting the chilly grip of winter while also foreshadowing the warmth that Sonoma will embrace in the following months.
In Sonoma, January stands out as one of the wettest months, receiving 125 mm (4.9 in) of precipitation over 9 days. This sets the stage for a rainy season, with February closely following at 127 mm (5.0 in), maintaining the trend of significant rainfall and a comparable number of wet days. As winter wanes into spring, the precipitation sharply declines, particularly in April and May, where totals drop to 36 mm (1.4 in) and 21 mm (0.8 in) respectively, signifying a transition towards drier months. The dry spell extends into the summer, with July and August experiencing absolutely no rain, while September sees a mere trace. As the year progresses into fall, the precipitation slightly picks up again, but remains minimal. This pattern highlights Sonoma's distinct wet winter and dry summer climate, punctuating the change of seasons with a striking contrast in rainfall.
In January, Sonoma experiences high humidity levels, averaging a substantial 86%. This trend of elevated moisture content persists into February and November, both of which see humidity remain above 80%, creating a damp ambiance during the winter months. As the seasons transition into spring, humidity gradually decreases, dipping to 80% in April and maintaining that level through May. The summer months bring even more relief, with levels decreasing further, reaching a comfortable 70% in July and dropping to 66% by August. However, September marks a slight uptick to 68%, before humidity begins to rise again as the year winds down. By December, the humidity returns to 84%, echoing the winter’s wet embrace. Overall, Sonoma's humidity demonstrates a clear seasonal pattern, with higher levels in winter and lower levels during the summer, creating a diverse climatic experience throughout the year.
In Sonoma, January experiences a moderate UV Index of 3, allowing for about 30 minutes of sun exposure before risking a burn. As winter transitions into spring, the UV Index steadily increases; by February, it rises to 5 and remains moderate, holding at 30 minutes of burn time. A more significant shift occurs in March, where the Index escalates to 7, entering the high exposure category and reducing the safe sun time to 25 minutes. The trend continues upward into the summer months, peaking in June and July with an extreme UV Index of 11, drastically dropping safe exposure to just 10 minutes. As the year progresses, the UV Index begins to decrease again in late summer and early fall, settling back to lower levels with 4 in November and 3 once more in December. This yearly fluctuation underscores the importance of monitoring UV levels for safe sun exposure. For more detailed information, check out Sonoma UV Index.
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January marks the beginning of the year in Sonoma, where the sun shines for 141 hours—a modest start that hints at the radiant days to come. As February rolls in, the daylight begins to stretch, offering 210 hours of sunshine, making way for an even brighter March with 257 hours. Spring arrives in April, ushering in a delightful 296 hours of sun, while May and June see a significant uptick, peaking with 384 hours in June. The sunny trend continues through the summer months, hitting its zenith in July with 394 hours of golden rays. As autumn approaches, the sunlight gently recedes—August offers 356 hours, followed by September's 314 hours. October brings a comforting 280 hours, yet hints at the seasonal shift, culminating in November's 220 hours and December's more reserved 185 hours. This beautiful ebb and flow of sunshine illustrates Sonoma's charm, balancing vibrant summers with serene winter days.
In Sonoma, United States, January ushers in a 39% chance of sunny weather, hinting at the seasonal transition from the coolness of winter to the warming promise of spring. This month stands at the lower end of the spectrum, with sunlight gradually becoming more frequent as the year progresses. The likelihood of sunshine increases significantly in February to 58%, continuing to climb through March at 63%, and reaching its peak by May, where 82% of days are sunny. As winter gives way to spring, those seeking brighter days will find reason for optimism, as each month following January showcases an upward trajectory in sunshine, culminating in the radiant summer months.
In Sonoma, January marks the start of the year with a modest daylight duration of 9 hours, inviting the gentle embrace of winter. As the month gives way to February, daylight extends to 10 hours, promising a hint of the growing warmth ahead. The progression continues into March, where daylight stretches to 11 hours, heralding the arrival of spring. This trend accelerates, culminating in the long, sun-soaked days of May and June, each boasting 14 hours of daylight. As summer wanes into August, the daylight gently recedes to 13 hours, then gradually contracts through fall and winter, returning to the 9 hours of January's quiet embrace. This rhythmic cycle not only underscores the changing seasons but also enhances the vibrant lifestyle enjoyed by Sonoma's residents.
As January unfolds in Sonoma, the average wind speed whistles in at a gentle 2.1 m/s (5 mph), setting a tranquil tone for the new year. This calm early winter breeze tends to give way to slightly brisker conditions in February and March, where the wind picks up to 2.5 m/s (6 mph) and 2.6 m/s (6 mph), respectively. As we transition into late spring, May showcases a notable increase, lifting the average to 3.2 m/s (7 mph), while June maintains a similar pace. However, the summer months see a gentle retreat, as July and August both drift back to 2.4 m/s and 2.2 m/s. By September and October, the winds remain consistently mild at around 2.1-2.3 m/s (5 mph), before dipping to their lowest in November at 1.6 m/s (4 mph). As the year closes, December ushers in a slight resurgence to 2.2 m/s (5 mph), hinting at a rhythmic cycle of breezes that define Sonoma’s seasonal character.
The weather in Sonoma changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of January'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.
January and February experience similar temperature ranges, with January having an average temperature of 10°C (50°F) and February slightly warmer at 11°C (52°F). Both months share a minimum temperature of -1°C (31°F), but February boasts a higher maximum temperature of 26°C (79°F) compared to January's 24°C (76°F). Precipitation levels are comparable, with January receiving 125 mm (4.9 in) over 9 days and February slightly more at 127 mm (5.0 in) across 8 days. Humidity remains high in both months, with January at 86% and February slightly lower at 84%. For more specific details on conditions, check out Sonoma weather in February.
January and March present distinct weather patterns, with January generally being cooler and wetter. In January, temperatures range from a chilly minimum of -1°C (31°F) to a maximum of 24°C (76°F), accompanied by substantial precipitation totaling 125 mm (4.9 in) over 9 days and high humidity at 86%. In contrast, March experiences a slight warming trend with minimum temperatures around 1°C (34°F) and maximums reaching 27°C (80°F), while precipitation decreases to 84 mm (3.3 in) over 10 days, accompanied by a modest humidity of 83%. For a more detailed look at March weather, check out Sonoma weather in March.
January weather is characterized by cooler temperatures, with minimums dropping to -1°C (31°F) and an average of 10°C (50°F), while the maximum can reach 24°C (76°F). This month also sees higher precipitation levels at 125 mm (4.9 in) over 9 days, contributing to a higher humidity of 86%. In contrast, April offers a noticeable warming trend, with minimum temperatures starting at 3°C (38°F) and an average rising to 14°C (58°F). The maximum in April can soar to 30°C (86°F), and the month experiences significantly less rainfall, totaling only 36 mm (1.4 in) over 5 days, leading to a slight drop in humidity to 80%. For more details on the specific conditions in April, you can visit Sonoma weather in April.
In January, the weather tends to be much cooler, with temperatures ranging from a brisk -1°C (31°F) at night to a pleasant 24°C (76°F) during the day, accompanied by significant precipitation of 125 mm (4.9 in) over approximately 9 days and high humidity at 86%. In contrast, May presents a much warmer and drier climate, with temperatures starting at a minimum of 5°C (41°F) and reaching up to 34°C (93°F) on warmer days. Precipitation drops substantially to just 21 mm (0.8 in) over 3 days, while humidity also decreases to 80%. This shift showcases the transition from the chill of winter to the warmth of late spring, making May a notably more pleasant month for outdoor activities. For a more detailed look at the weather during this time, check out Sonoma weather in May.
In January, the weather is quite chilly with minimum temperatures dipping to -1°C (31°F), and average highs reaching only 24°C (76°F). The month experiences significant precipitation, totaling 125 mm (4.9 in) over nine days, contributing to a high humidity level of 86%. In contrast, June boasts a much warmer climate, with minimum temperatures starting at 10°C (50°F) and maximums soaring to 37°C (99°F). Remarkably, June is exceptionally dry, recording just 1 mm of precipitation over the entire month, and humidity decreases to 76%. For a more detailed look at the June weather, you can visit Sonoma weather in June.
January and July present stark contrasts in weather. In January, temperatures range from a chilly minimum of -1°C (31°F) to a mild average of 10°C (50°F), reaching a maximum of 24°C (76°F). This month is characterized by significant precipitation, with around 125 mm (4.9 in) falling over 9 days, and humidity levels are notably high at 86%. In contrast, July experiences much warmer conditions, with temperatures starting at a minimum of 11°C (53°F) and peaking at a sizzling maximum of 36°C (96°F), averaging around 20°C (68°F). Remarkably, July sees no recorded precipitation, with dry days and lower humidity at 70%. For more detailed information on weather patterns, check out Sonoma weather in July.
In January, the weather tends to be much cooler, with temperatures ranging from a minimum of -1°C (31°F) to a maximum of 24°C (76°F), and an average temperature of 10°C (50°F). This month sees significant precipitation, totaling 125 mm (4.9 inches) over nine days, accompanied by high humidity levels at 86%. In contrast, August brings much warmer conditions, with temperatures ranging from a minimum of 11°C (52°F) to a scorching maximum of 36°C (98°F), and an average of 20°C (68°F). Notably, August is dry, boasting no recorded precipitation and only 66% humidity. For those curious about the warm, dry weather typical of summer, check out Sonoma weather in August.
In comparing the weather between January and September, there is a striking contrast in both temperature and precipitation. January experiences cooler temperatures, with an average of 10°C (50°F) and a maximum of 24°C (76°F), along with substantial rainfall of about 125 mm (4.9 in) across nine days and high humidity at 86%. In contrast, September enjoys significantly warmer temperatures, with an average of 20°C (68°F) and a peak reaching up to 39°C (102°F). Furthermore, September is exceptionally dry, reporting only 1 mm (0.0 in) of precipitation over the month, with no rainy days and a more comfortable humidity level of 68%. For more detailed insights, you can check Sonoma weather in September.
In January, the weather is typically colder, with temperatures ranging from a minimum of -1°C (31°F) to a maximum of 24°C (76°F) and an average of 10°C (50°F). It is characterized by higher precipitation, receiving about 125 mm (4.9 inches) over approximately 9 days, and the humidity is quite high at 86%. In contrast, October offers milder conditions, with temperatures varying from a minimum of 4°C (40°F) to a maximum of 34°C (94°F), and an average of 17°C (63°F). The month sees significantly less rainfall, totaling just 33 mm (1.3 inches) over 2 days, resulting in lower humidity levels at 72%. For more specific insights into the climate, you can check Sonoma weather in October.
In comparing the weather between January and November, January typically features cooler temperatures with a minimum of -1°C (31°F) and an average of 10°C (50°F), peaking at 24°C (76°F). Additionally, January experiences more precipitation, averaging 125 mm (4.9 in) over about 9 days, with a higher humidity level of 86%. In contrast, November offers slightly milder temperatures, with a minimum of 1°C (33°F) and an average of 12°C (55°F), reaching a maximum of 27°C (81°F). Precipitation is considerably less during November, totaling around 50 mm (2.0 in) over 5 days, and humidity remains relatively low at 84%. For more detailed insights into November weather, you can explore Sonoma weather in November.
In January, the weather features a slight dip in minimum temperatures, averaging around -1°C (31°F), while December starts at a minimum of 0°C (33°F). Both months share an average temperature of 10°C (50°F), but January can reach a higher maximum of 24°C (76°F) compared to December's 23°C (73°F). Precipitation levels are higher in January at 125 mm (4.9 in) vs. December's 94 mm (3.7 in), with both months experiencing rainfall on approximately nine days. Humidity is slightly elevated in January at 86% compared to December’s 84%. For more details on the December climate, you can check Sonoma weather in December.
As we wrap up our exploration of Sonoma's January weather, this month stands out with its cool temperatures and notable precipitation. Compared to the warmer and drier summer months, January offers a refreshing chill, with average temperatures significantly lower and occasional cold snaps dipping near freezing. The high humidity and frequent rainy days create a lush and vibrant landscape that starkly contrasts the sun-drenched conditions of the later seasons. This unique climate makes January a time of cozy indoor gatherings and serene outdoor strolls amidst the dripping vines. For a deeper dive into how January fits into the broader picture of Sonoma's climate, check out Sonoma Climate.