Last updated: February 24, 2025
In Mill Valley, United States, January brings a varied climate characterized by a maximum temperature of 23°C (73°F), an average of 10°C (51°F), and a chilly minimum of 0°C (33°F). The month experiences significant precipitation, totaling 111 mm (4.4 in) over 8 days, contributing to a lush winter landscape. With humidity levels averaging around 85%, January's weather presents a refreshing, albeit damp atmosphere, perfect for those who revel in the crispness of winter.
In January, temperatures in Mill Valley, United States, showcase a cool yet lively winter climate, with minimums around 0°C (33°F) and an average of 10°C (51°F), peaking at a pleasant 23°C (73°F). This month marks the onset of the year with mild days and crisp nights, offering a stark contrast to the warmer months ahead. As we transition into February, the weather remains relatively stable, with slight increases in both minimum and average temperatures. Notably, the maximum temperature holds steady at 23°C (73°F), indicating a gentle consistency in the region's winter warmth. As winter progresses into spring, the gradual rise in temperatures becomes evident, suggesting a trend of increasing warmth with an anticipated shift towards the vibrant and warmer months just around the corner.
In January, Mill Valley receives an average precipitation of 111 mm (4.4 in) over 8 days, marking it as one of the wetter months of the year. Following January, precipitation slightly increases in February with 116 mm (4.6 in), maintaining the same number of rainy days. However, as the seasons shift into spring, both the amount of rainfall and the frequency of rainy days begin to decline sharply, dropping to 80 mm (3.1 in) in March and plummeting to just 35 mm (1.4 in) by April. This trend continues into the warmer months, where summer barely sees any rain, culminating in virtually dry June and July. The year then wraps up with a gradual resurgence in precipitation during the fall, as October and November bring 30 mm (1.2 in) and 48 mm (1.9 in), respectively, before another wet December brings 98 mm (3.9 in). Overall, this data underscores a distinct seasonal pattern: wet winters, dry summers, and a moderate transition into the fall.
In Mill Valley, January greets residents with high humidity levels averaging at 85%, setting the tone for the winter months. As the year progresses into February and March, humidity remains slightly consistent at 82%, offering a brief respite as spring approaches. Notably, April sees a slight dip to 79%, marking a transition into drier conditions. However, as summer arrives in June, humidity rises again, peaking at 87% in both July and August, which creates a warm, muggy atmosphere. Following the summer months, September maintains a high humidity level of 86%, but as fall sets in, a gradual decline occurs, bringing the levels down to 80% in October and further to 79% by December. This cyclical trend illustrates the region's fluctuating humidity, with a significant rise during the summer and a notable decrease as the year winds down.
In Mill Valley, January sees a moderate UV Index of 3, allowing for about 30 minutes of safe sun exposure before the risk of burning increases. As winter transitions to spring, the UV Index steadily rises, peaking in May with an extreme level of 10, where just a 15-minute outing can lead to skin damage. This upward trend continues into the summer months of June and July, maintaining an extreme index of 11 and requiring even shorter sun exposure times. As autumn arrives, the index notably decreases, with November and December reverting back to a moderate level of 3. This fluctuation highlights the importance of monitoring the UV Index throughout the year to protect your skin while enjoying the beautiful California sunshine. For more details, visit Mill Valley UV Index.
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In Mill Valley, United States, January welcomes just 148 hours of sunshine, marking it as one of the cloudier months. However, as winter fades, the days grow longer and brighter, with February bringing a notable increase to 215 hours. The sun continues to shine more generously as spring approaches, peaking in May and June with an impressive 356 and 378 hours, respectively. The warm summer months keep the sunlight spilling in, with July reaching a delightful 386 hours. As the seasons transition into autumn, the hours slowly decline, with September still enjoying a robust 312 hours before falling to 224 in November. By December, the year winds down with 191 hours of sunshine, illustrating a clear seasonal rhythm that invites residents and visitors alike to embrace the distinct beauty each month offers.
In Mill Valley, January brings a 39% chance of sunny weather, marking it as one of the cloudier months of the year. As winter unfolds, the likelihood of sunshine gradually increases, with February rising to 56% and continuing to climb steadily through the spring months. By March, the sun graces the town 63% of the time, and by April, this figure grows to an encouraging 66%. Such trends highlight a shift towards a sunnier outlook as the year progresses, culminating in May's 75% probability. This trajectory not only sets the stage for brighter days ahead but also reflects the natural transition from the chill of winter to the warmth of spring, making January a transitional month in the cycle of Mill Valley's weather patterns.
In Mill Valley, United States, the month of January brings a modest 9 hours of daylight, marking the start of the year with shorter days. As winter transitions into spring, daylight gradually increases, reaching a delightful 10 hours in February and 11 hours in March. This upward trend continues into the vibrant months of April and May, where residents can bask in 13 and 14 hours of daylight, respectively. Interestingly, this peak of 14 hours continues through June and July, offering ample time for outdoor activities and exploration. As summer wanes, the duration begins to recede slightly, with 13 hours in August and tapering down to 12 hours in September. The descent into fall sees daylight wane further, dropping to 11 hours in October and 10 hours in November, before concluding the year in December once again with 9 hours of daylight. This cyclical pattern not only highlights the seasonal rhythms of Mill Valley but also sets the stage for residents to embrace the changing nature of light throughout the year.
In Mill Valley, January ushers in a gentle breeze, with an average wind speed of 2.8 m/s (6 mph), setting a calm tone for the year. As winter transitions to spring, a gradual uptick in wind speed is observed, peaking in April at 4.1 m/s (9 mph), before stabilizing in the summer months. Interestingly, the winds in May reach 4.8 m/s (11 mph), hinting at the transition to warmer days. The summer breezes, while slightly declining, maintain a soothing presence, with speeds hovering around 3.8 m/s (9 mph) in July. As the seasons shift into fall, there's another noticeable decline, culminating in November’s 2.2 m/s (5 mph), the calmest month. This pattern illustrates the rhythmic ebb and flow of wind in Mill Valley, beautifully mirroring the changing seasons and inviting residents and visitors alike to embrace the unique atmosphere each month brings.
The weather in Mill Valley 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 Mill Valley and find detailed weather information for every month.
In January, the weather sees a minimum temperature of 0°C (33°F) and an average of 10°C (51°F), reaching a maximum of 23°C (73°F). This month experiences 111 mm (4.4 in) of precipitation over 8 days, with a humidity level averaging 85%. In contrast, February offers slightly warmer conditions, with a minimum temperature of 2°C (35°F) and an average of 11°C (52°F), while still reaching a maximum of 23°C (73°F). February also has a bit more rainfall, totaling 116 mm (4.6 in), but maintains the same number of precipitation days at 8, with humidity slightly lower at 82%. For more details, you can check Mill Valley weather in February.
January and March exhibit noticeable differences in weather patterns. January has a cooler average temperature ranging from a minimum of 0°C (33°F) to a maximum of 23°C (73°F), while March shows a slight warming trend with temperatures starting at 4°C (39°F) and peaking at 24°C (75°F). Precipitation is higher in January, with 111 mm (4.4 in) over 8 days, compared to March's 80 mm (3.1 in) over 10 days. Humidity levels are relatively similar, with January at 85% and March slightly lower at 82%. For more detailed insights, check out Mill Valley weather in March.
In January, the weather is cooler, with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 23°C (73°F), and an average of 10°C (51°F). The month sees considerable rainfall, with 111 mm (4.4 in) of precipitation over 8 days, contributing to high humidity levels at 85%. In contrast, April experiences milder temperatures, with a minimum of 4°C (40°F), an average of 14°C (57°F), and a maximum of 28°C (83°F). Precipitation decreases significantly to 35 mm (1.4 in) over just 5 days, and humidity drops slightly to 79%. For a more detailed look at April weather, check out Mill Valley weather in April.
In January, the weather is significantly cooler, with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 23°C (73°F) and an average of 10°C (51°F). The month experiences substantial rainfall, totaling 111 mm (4.4 in) over about 8 days, contributing to a high humidity level of 85%. In stark contrast, May brings warmer temperatures with a minimum of 7°C (45°F), an average of 15°C (60°F), and a maximum of 30°C (86°F). Rainfall decreases dramatically to just 20 mm (0.8 in) over 2 days, and humidity remains fairly steady at 83%. For more insight into the delightful weather of May, check out Mill Valley weather in May.
January and June present strikingly different weather conditions. In January, temperatures typically range from a chilly 0°C (33°F) to a mild 23°C (73°F), with an average of 10°C (51°F), accompanied by 111 mm (4.4 in) of precipitation over 8 days and a high humidity of 85%. In contrast, June offers a more pleasant climate, with temperatures starting at a minimum of 10°C (51°F) and peaking at a warm 32°C (90°F), averaging 17°C (63°F). Notably, June sees significantly less precipitation, with only 2 mm (0.1 in) expected and no rainy days, combined with a humidity level slightly lower at 84%. For more details about weather in the summer, check out Mill Valley weather in June.
January and July present striking differences in weather patterns. In January, temperatures range from a chilly 0°C (33°F) to a pleasant 23°C (73°F), with an average of 10°C (51°F). The month experiences considerable precipitation, with 111 mm (4.4 in) falling over eight days, and humidity levels are high at 85%. In contrast, July offers a much warmer climate, where temperatures vary from a minimum of 11°C (52°F) to a maximum of 30°C (87°F), averaging 17°C (63°F). Remarkably, July sees little to no rainfall, with only 2 mm (0.1 in) recorded and no rainy days, while humidity rises slightly to 87%. For more specifics on July weather, you can check Mill Valley weather in July.
In January, temperatures in Mill Valley range from a chilly minimum of 0°C (33°F) to a pleasant maximum of 23°C (73°F), with an average of 10°C (51°F). This month is characterized by substantial precipitation, with around 111 mm (4.4 in) falling over 8 days, and high humidity at 85%. In contrast, August presents a much warmer climate, with temperatures starting at a minimum of 11°C (52°F) and reaching a high of 32°C (90°F), averaging at 18°C (64°F). Remarkably, August experiences very little precipitation, with only 1 mm (0.1 in) recorded over 0 days, while humidity remains slightly higher at 87%. For further details on August weather, visit Mill Valley weather in August.
In January, the weather is cooler with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 23°C (73°F), averaging around 10°C (51°F). This month also sees significant precipitation, with 111 mm (4.4 in) falling over approximately 8 days, coupled with high humidity levels at 85%. In contrast, September offers a much warmer climate, with temperatures ranging from a minimum of 9°C (49°F) to a scorching maximum of 36°C (98°F), averaging 18°C (65°F). Remarkably, September experiences nearly no rainfall, recording only 2 mm (0.1 in) over 0 days, and maintains a slightly higher humidity of 86%. For more details, check Mill Valley weather in September.
In January, the weather features a wider range of temperatures, with a minimum of 0°C (33°F) and a maximum reaching up to 23°C (73°F), averaging around 10°C (51°F). This month experiences significant precipitation of 111 mm (4.4 in) over approximately 8 days, accompanied by high humidity levels of 85%. In contrast, October presents milder conditions, with temperatures ranging from a minimum of 6°C (44°F) to a maximum of 31°C (88°F), averaging at 16°C (62°F). The month sees much less rainfall, totaling 30 mm (1.2 in) over just 2 days, and slightly lower humidity at 80%. For more details, visit Mill Valley weather in October.
In comparing the weather between January and November, January tends to be cooler, with average temperatures ranging from a minimum of 0°C (33°F) to a maximum of 23°C (73°F), while November sees slightly higher temperatures, with a minimum of 3°C (37°F) and a maximum of 25°C (77°F). Additionally, January experiences more precipitation, totaling 111 mm (4.4 in) over 8 days, compared to November's 48 mm (1.9 in) over just 5 days. The humidity is also higher in January at 85%, compared to November's 79%. For more details on the weather specific to November, you can check Mill Valley weather in November.
In comparing the weather of January and December, we find that both months have similar average temperatures, hovering around 10°C (51°F). However, January tends to be slightly chillier, with minimum temperatures dropping to 0°C (33°F) compared to December's minimum of 3°C (38°F). Additionally, January experiences more precipitation, totaling 111 mm (4.4 in) over 8 days, while December sees a bit less at 98 mm (3.9 in) over 9 days. Humidity levels are higher in January at 85%, compared to December's 79%, contributing to a generally cooler and wetter atmosphere in the new year. For more detailed insights about the weather patterns, you can refer to Mill Valley weather in December.
In January, Mill Valley experiences a unique blend of cool temperatures and significant precipitation, setting it apart from the warmer and drier months of the year. With average highs reaching around 10°C and a notable humidity level of 85%, the month can feel quite brisk, particularly in the evenings. While precipitation is relatively frequent, with about 8 rainy days, this is part of what makes the lush landscape so vibrant. Such climatic conditions create a cozy atmosphere, inviting residents and visitors alike to embrace the beauty of Mill Valley's winter scenery. For a deeper dive into the area's weather patterns throughout the year, visit Mill Valley Climate.