Last updated: February 24, 2025
March in Napa, United States, ushers in a transition marked by mild temperatures and increased humidity. With a maximum of 30°C (87°F) and a minimum of 1°C (34°F), the month boasts an average temperature of 12°C (55°F), making it a comfortable time for outdoor activities. However, nature also brings its share of surprises, as 81 mm (3.2 in) of precipitation falls over 9 days, leading to vibrant landscapes and flourishing vineyards. The air holds a notable humidity level of 83%, creating a refreshing ambiance that enhances the beauty of Napa's renowned wine country in early spring.
March in Napa, United States, marks a transition into the heart of spring, as temperatures begin to rise significantly. With a minimum of 1°C (34°F) and a pleasant average of 12°C (55°F), the month provides a refreshing contrast to the chill of winter. The maximum temperatures can reach up to 30°C (87°F), hinting at the warmer days ahead. This steady increase in warmth is evident when compared to the preceding months, where January and February showcase much cooler ranges. As the landscape begins to bloom with life, March welcomes visitors with mild, enjoyable weather, promising an ideal setting for wine tasting and outdoor adventures in the beautiful Napa Valley.
In March, Napa experiences a notable reduction in precipitation, with 81 mm (3.2 in) of rain spread over 9 days. This month marks a clear transition from the wetter winter months of January and February, which see significantly higher rainfall (119 mm and 113 mm, respectively). As spring approaches, the skies begin to clear, paving the way for drier conditions ahead, evidenced by April's drop to just 33 mm (1.3 in). The trend reflects a typical shift in Napa's climate, where the robust rains of winter gradually give way to the dry spell of summer, culminating in zero precipitation by July and August. As March unfolds, it acts as a bridge, gently ushering in the drier seasons while still holding onto remnants of winter's embrace.
In March, Napa experiences a slight dip in humidity, with levels averaging 83%, compared to a steady 84% in the preceding months of January and February. This minor decrease sets the stage for the gradual decline that follows as spring transitions into summer. April sees humidity drop further to 81%, and by May, a more significant shift occurs, bringing it down to 74%. This trend indicates a consistent decrease as warmer months approach, with July and August boasting dramatically lower levels at 44% and 36%, respectively. Overall, Napa’s March humidity serves as a transitional phase, hinting at the seasonal shift towards drier, more comfortable conditions that characterize the summer months.
As March unfolds in Napa, the UV Index rises to 7, indicating a high exposure category. This marks a notable shift from the previous months, where the UV Index hovered around moderate levels of 3 in January and 5 in February. With a burn time of just 25 minutes, it's essential to take precautions if you plan to spend time outside, especially as the sun's intensity becomes more pronounced. This trend continues into April, where the UV Index spikes further to 9, emphasizing the importance of skin protection as we transition into the sunnier months. As always, stay informed about the Napa UV Index to ensure safe outdoor activities.
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As March rolls into Napa, the sun starts to shine generously, marking a significant leap in daylight hours. With 257 hours of sunshine, March transitions from the winter months, where hours were low at 141 in January and 210 in February, to a vibrant beginning of spring. This rising trend continues into April with even more sunny days, peaking in the summer months. The increase in sunlight not only brightens the vineyards but also warms the atmosphere, invigorating both the landscape and the spirits of locals and visitors alike. March serves as a beautiful precursor to the sun-drenched days that follow, reflecting Napa's charm and allure as the seasons change.
March marks a delightful transition in Napa's climate, showcasing a 63% chance of sunny weather. This increase from February’s 58% reflects a gradual shift towards sunnier days as spring approaches. As the month unfolds, the sun's embrace strengthens, paving the way for even brighter prospects in April, which boasts a 70% likelihood of sunshine. This upward trend continues into May and June, where the chances soar to 82%, creating a picturesque setting for outdoor activities and vineyard visits. With each passing month leading to summer, the likelihood of clear skies enhances, inviting both locals and visitors to savor Napa's sun-kissed landscapes.
As spring unfolds in March, Napa experiences a delightful increase in daylight duration, with the sun gracing the skies for 11 hours each day. This shift marks a turning point in the year, as the days grow progressively longer, setting the stage for the abundant sunshine of April and May. Following the 10 hours of daylight in February, March's additional hour not only brightens the landscape but also invites outdoor activities and exploration. This trend of increasing daylight continues steadily, peaking in the summer months before gradually tapering off again in autumn. Thus, March heralds the vibrant awakening of nature, accompanied by lengthening days that enhance the beauty and allure of Napa.
As March sweeps into Napa, residents and visitors alike can expect a slight uptick in the breezy conditions, with average wind speeds creeping up to 2.5 m/s (6 mph). This gentle increase from February's 2.4 m/s (5 mph) signals the arrival of spring, where the whispers of wind mingle with blooming vines, invigorating the famed vineyards. March stands at the threshold of another seasonal shift, laying the groundwork for even brisker winds in the coming months, as April nudges the average to 2.7 m/s (6 mph). It's a time when the air feels fresher and the scenery comes alive, making it an ideal backdrop for outdoor adventures and leisurely wine tastings under the sun.
The weather in Napa changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of March's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Napa and find detailed weather information for every month.
March typically experiences milder temperatures compared to January, with average highs reaching up to 30°C (87°F) compared to January's max of 25°C (77°F). While March has a comfortable average temperature of 12°C (55°F), January's average is slightly cooler at 10°C (50°F). Precipitation is higher in January with 119 mm (4.7 in) over 8 days, while March receives 81 mm (3.2 in) over 9 days, making March slightly wetter despite the lower total. Both months exhibit high humidity levels, with March at 83% and January at 84%, creating a consistently moist atmosphere. For more detailed insights on January weather, check out Napa weather in January.
In comparing the weather between March and February, we observe that March generally brings slightly warmer temperatures, with a minimum of 1°C (34°F) compared to February's minimum of -1°C (30°F). The average temperature in March is 12°C (55°F), just a degree above February's 11°C (53°F), while March's maximum temperature reaches 30°C (87°F), surpassing February's high of 27°C (80°F). Interestingly, while March sees a decrease in total precipitation to 81 mm (3.2 in) over 9 days, February has a higher total at 113 mm (4.5 in) across 7 days. Humidity levels remain relatively stable, with March at 83% and February slightly higher at 84%. For more detailed insights into February's weather, you can check Napa weather in February.
In comparing the weather of March and April, it's evident that April tends to be slightly warmer and drier. March experiences a temperature range from a minimum of 1°C (34°F) to a maximum of 30°C (87°F), with an average temperature of 12°C (55°F) and 81 mm (3.2 in) of precipitation over 9 days. In contrast, April shows a modest increase in average temperature to 15°C (60°F), with minimum and maximum temperatures ranging from 3°C (38°F) to 33°C (92°F). Furthermore, April has significantly less precipitation, totaling only 33 mm (1.3 in) across just 5 days. Humidity levels remain fairly consistent, averaging around 81% for both months. For more detailed information, you can check Napa weather in April.
March and May exhibit notable differences in weather patterns. In March, temperatures range from a chilly minimum of 1°C (34°F) to a warmer maximum of 30°C (87°F), with an average temperature of 12°C (55°F). The month is characterized by higher precipitation of 81 mm (3.2 in) over about 9 days, contributing to a humidity level of 83%. In contrast, May offers more stable and warmer weather, featuring a minimum temperature of 5°C (41°F) and a maximum of 37°C (99°F), with an average of 18°C (64°F). Precipitation significantly decreases to just 19 mm (0.8 in), falling over only 2 days and leading to a lower humidity rate of 74%. For more detailed insights, check out Napa weather in May.
March and June present strikingly different weather conditions. In March, temperatures range significantly from a chilly minimum of 1°C (34°F) to a warm maximum of 30°C (87°F), with an average temperature of 12°C (55°F). This month also sees a considerable amount of precipitation, with around 81 mm (3.2 in) falling over about 9 days, contributing to a high humidity level of 83%. In contrast, June boasts a much milder climate, with minimum temperatures starting at 10°C (51°F) and soaring to a scorching maximum of 41°C (106°F), averaging 21°C (70°F). Notably, precipitation is minimal in June, with only 2 mm (0.1 in) recorded and no rainy days, leading to a lower humidity of 64%. For a detailed look at the weather during this month, check out Napa weather in June.
March and July present contrasting weather patterns. In March, temperatures range from a crisp minimum of 1°C (34°F) to an average of 12°C (55°F), occasionally peaking at 30°C (87°F). The month is also characterized by significant precipitation, averaging 81 mm (3.2 in) over 9 days, resulting in a high humidity level of 83%. In stark contrast, July experiences much warmer temperatures with a minimum of 11°C (53°F) and an average of 21°C (70°F), soaring to a maximum of 40°C (104°F). Notably, July is dry, witnessing no precipitation at all, contributing to a more comfortable humidity level of 44%. For more detailed information on weather in July, check out Napa weather in July.
March and August present stark contrasts in weather patterns. In March, temperatures range from a chilly minimum of 1°C (34°F) to a pleasant average of 12°C (55°F), with the potential to peak at a warm 30°C (87°F). This month also sees substantial precipitation, averaging 81 mm (3.2 in) over about nine days, accompanied by high humidity levels of 83%. In contrast, August boasts significantly warmer temperatures, with a minimum of 12°C (53°F), an average of 21°C (71°F), and maximum highs reaching a scorching 42°C (108°F). Notably, August experiences no precipitation and remarkably low humidity at just 36%, making it a dry and hot month. For more insights, check out Napa weather in August.
March and September showcase distinct differences in weather patterns. In March, temperatures range from a chilly minimum of 1°C (34°F) to a pleasant average of 12°C (55°F), with occasional highs reaching up to 30°C (87°F). This month experiences considerable precipitation, averaging 81 mm (3.2 in) over about 9 days, accompanied by high humidity levels at 83%. In contrast, September boasts warmer temperatures, starting with a minimum of 8°C (46°F) and averaging 21°C (70°F), with extreme highs peaking at a scorching 44°C (111°F). Notably, rainfall is scarce in September, with an average of just 1 mm (0.0 in) and no rainy days, leading to a much lower humidity level of 44%. For more detailed insights, check out Napa weather in September.
March and October present contrasting weather patterns, showcasing the transition from early spring to late autumn. In March, temperatures range from a chilly 1°C (34°F) to a warm maximum of 30°C (87°F), while the average temperature hovers around 12°C (55°F). This month also sees significant rainfall, with precipitation totaling 81 mm (3.2 in) across approximately 9 days, contributing to a high humidity level of 83%.
In contrast, October boasts milder temperatures, with a minimum of 4°C (40°F) and a higher average of 18°C (65°F), reaching up to a sweltering 36°C (98°F) at times. Rainfall is sparse, with only 29 mm (1.1 in) over about 2 days, leading to a considerably lower humidity of 65%. For a detailed insight into October's climate, check out Napa weather in October. Overall, while March is marked by cooler, wetter conditions, October offers warmer, drier weather.
March and November share a similar range of temperatures, with both months featuring minimums around 1°C (34°F) and 0°C (32°F), respectively, and maximums that reach up to 30°C (86-87°F). However, March tends to be wetter, with precipitation of 81 mm (3.2 inches) over approximately 9 days, compared to November's 43 mm (1.7 inches) across just 5 days. Humidity levels are quite close, with March at 83% and November at 84%. Overall, while both months can experience warm temperatures, March often brings more rain than November. For more details, you can check Napa weather in November.
When comparing the weather in March and December, both months exhibit relatively mild temperatures, but March is generally warmer, with a minimum of 1°C (34°F) and an average temperature of 12°C (55°F), peaking at 30°C (87°F). In contrast, December has a minimum temperature of 0°C (32°F) and an average of 10°C (50°F), with a maximum of 24°C (75°F). Both months experience similar precipitation levels, with March receiving 81 mm (3.2 in) and December slightly higher at 91 mm (3.6 in), both spread over nine days. The humidity remains constant at 83% for both months, contributing to the overall mild and occasionally damp conditions typical for this region. For a detailed look into December's weather, check Napa weather in December.
March in Napa is a transitional month, where winter's chill begins to fade, making way for the budding warmth of spring. While daytime temperatures can reach a pleasant 30°C (87°F), the nights still hold onto the coolness, dipping as low as 1°C (34°F). This variability, combined with an average humidity of 83%, adds a refreshing crispness to the air. Rain is still a part of the equation, with 81 mm (3.2 in) of precipitation scattered over 9 days, indicating that while the landscape flourishes, the occasional shower keeps nature vibrant. For a deeper understanding of the region's weather patterns, be sure to explore the full Napa Climate page.