Last updated: February 24, 2025
December in Palo Alto, United States, presents a mild yet refreshing climate characterized by a maximum temperature reaching 22°C (72°F) and an average of 11°C (52°F). The month is punctuated by cool nights, with temperatures dropping to a brisk minimum of 3°C (37°F). Precipitation is a notable feature, with a total of 88 mm (3.5 in) spread over 9 days, resulting in an 80% humidity level that adds a touch of crispness to the air. As the season shifts, this month offers a unique blend of cool temperatures and refreshing rain, making it a transitional time in the region.
In Palo Alto, December ushers in the chill of winter, with temperatures reflecting a subtle downward trend as the year winds down. The month features a minimum temperature of 3°C (37°F), while average daily highs reach around 22°C (72°F), creating a mild yet crisp atmosphere perfect for outdoor activities. Generally, December maintains an average temperature of 11°C (52°F), similar to the preceding months, indicating the city's relatively stable climate. Coupled with the cooler evenings, the pleasant daytime warmth invites both residents and visitors to enjoy the serene surroundings before the year concludes.
In December, Palo Alto experiences a notable increase in precipitation, contributing to the region's moisture-rich winter months. With 88 mm (3.5 in) of rain falling over 9 days, December stands as a significant peak compared to the drier summer months, which see little to no rainfall. This pattern of increased precipitation sets the tone for the transition into the wet season, following November's 47 mm over 5 days. This upward trend in rainfall as the year closes out emphasizes the importance of December in replenishing local ecosystems and preparing the region for the following months of more consistent rain. As winter continues, residents can expect the precipitation to play a vital role in both environmental health and water resource management.
As December settles in Palo Alto, the humidity tends to hold steady at around 80%, creating a cool, crisp atmosphere that contrasts with the warmer months. Following the trend of the preceding months, November's 78% humidity gives way to a slight increase as the year wraps up. Interestingly, this seasonal shift reflects the higher humidity levels typical of the winter months, yet remains notably lower than the peak humidity experienced in the earlier part of the year. Throughout the months, humidity has consistently decreased since the summer, highlighting a significant drop from the 54% in August to December's 80%. This gradual transition underscores the charm of Palo Alto's climate as it moves from the dryness of summer into a more humid and refreshing winter.
In December, the UV Index in Palo Alto drops back to a moderate level of 3, mirroring the relatively low exposure seen in January and November. With a burn time of about 30 minutes, it's a welcome reprieve after the extreme conditions of summer months, which boasted values as high as 11 in June and July. As we transition from the high UV levels of late spring and summer, December offers a safer window for outdoor activities, encouraging residents to enjoy the cooler weather while still being mindful of sun exposure. For more information on UV ratings throughout the year, feel free to check out Palo Alto UV Index.
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As the year draws to a close, December in Palo Alto graces residents with a comforting 194 hours of sunshine, a notable dip from the sun-drenched peak of June with its impressive 355 hours. While summer months bask in the warmth of abundant sunlight, the city transitions into the cooler season with a steady decline from May onwards, reaching its annual low in the heart of winter. Despite this decrease, December's sunlit hours still offer a delightful contrast to the frosty bite of the season, inviting a sense of warmth and hope as the community prepares for the new year ahead. The overall trend beautifully illustrates Palo Alto's diverse climate—a region where sunshine dances through each month, wrapping its inhabitants in the golden glow of leisure and serenity.
In Palo Alto, the likelihood of sunny weather in December takes a dip, with only a 35% chance of sunshine. This marks a notable departure from the sunnier months that lead into the year, particularly May and August, which boast probabilities over 60%. As winter approaches, the pattern clearly shows a gradual decline in sunny days, reaching its low point in December. Following a relatively bright fall, with November at 46%, the shift to the year's end highlights a trend towards more overcast and potentially wetter days, making December one of the cloudier months to experience in this Californian locale.
In Palo Alto, December marks a return to shorter days, with daylight lasting approximately 9 hours. This shift is part of a clear trend observed throughout the year, where daylight duration gradually increases from the depths of winter in January, peaking at 14 hours during the summer months of May through July. As the year transitions from fall to winter, daylight diminishes from 11 hours in October to December's low, highlighting the seasonal ebb and flow. Despite the shorter days, December offers a cozy ambience, inviting residents to savor the festive season as they anticipate the gradual return of longer days in the new year.
As December descends upon Palo Alto, the average wind speed settles at 2.4 m/s (5 mph), maintaining the gentle breezes characteristic of the season. Reflecting a slight increase from November's 1.8 m/s (4 mph), the winds in December echo a broader trend observed throughout the year. After peaking in May with an average of 3.0 m/s (7 mph), the wind speeds tend to drift downward during the late summer and early fall, with September recording the year’s lowest at 2.0 m/s (4 mph). However, the cooling December air ushers in a modest resurgence, lending a refreshing touch to the winter season without the harsh gusts often found elsewhere. This subtle yet pleasant wind reminds us that even in the colder months, Palo Alto retains its charm, inviting residents to savor the outdoors.
The weather in Palo Alto 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 Palo Alto and find detailed weather information for every month.
In December, temperatures range from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), with an average temperature of 11°C (52°F). The month experiences 88 mm (3.5 in) of precipitation over 9 days, coupled with a humidity level of 80%. Similarly, January sees a slight drop in minimum temperature to 2°C (36°F), while the maximum temperature increases to 24°C (75°F), maintaining the same average of 11°C (52°F). However, January is wetter, with precipitation rising to 105 mm (4.1 in) over 7 days and humidity slightly increasing to 82%. For more detailed insights into January weather, check out Palo Alto weather in January.
When comparing the weather in December and February, we can see some interesting similarities and differences. December features a temperature range with a minimum of 3°C (37°F) and a maximum of 22°C (72°F), while February has slightly cooler mornings with a minimum of 2°C (36°F) but can reach a higher maximum of 24°C (76°F). Precipitation is somewhat similar, with December receiving 88 mm (3.5 in) over 9 days and February experiencing a slightly higher total of 100 mm (3.9 in) across 8 days. Additionally, February tends to be a bit more humid, averaging 84% compared to December's 80%. For a more detailed overview of February weather, you can check out Palo Alto weather in February.
December and March in Palo Alto showcase subtle yet distinct differences in weather patterns. December typically experiences slightly cooler temperatures, with averages ranging from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), while March warms up just a notch, with minimums of 4°C (40°F) and maximums hitting 25°C (78°F). Precipitation levels are similar, with December seeing 88 mm (3.5 in) over about 9 days and March slightly less at 86 mm (3.4 in) over 11 days. Humidity remains high in both months, with December at 80% and March at 82%. For a more detailed comparison, you can check Palo Alto weather in March.
In December, the weather tends to be cooler, with temperatures ranging from a minimum of 3°C (37°F) to a maximum of 22°C (72°F) and an average of 11°C (52°F). This month also sees higher precipitation, with about 88 mm (3.5 in) falling over 9 days, and humidity levels averaging around 80%. In contrast, April experiences milder temperatures, with lows of 6°C (42°F) and highs reaching up to 30°C (87°F), resulting in an average of 13°C (57°F). Additionally, rainfall is significantly lower in April, totaling just 33 mm (1.3 in) over 5 days and slightly reduced humidity at 78%. For more detailed information about April weather, you can visit Palo Alto weather in April.
December and May present quite different weather characteristics. In December, temperatures range from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), with an average of 11°C (52°F). This month also sees significant precipitation, with about 88 mm (3.5 in) falling over nine days and a humidity level of 80%. In contrast, May offers warmer temperatures, with minimums of 8°C (46°F) and maximums reaching 29°C (84°F), averaging around 15°C (59°F). The month is much drier, with only 24 mm (0.9 in) of rain over just two days, and humidity levels at a more comfortable 71%. For more detailed insights about May weather specifically, check out Palo Alto weather in May.
In December, the weather is considerably cooler, with temperatures ranging from a minimum of 3°C (37°F) to a maximum of 22°C (72°F) and averaging around 11°C (52°F). The month sees an average of 88 mm (3.5 inches) of precipitation, spread over approximately 9 days, resulting in a higher humidity level of 80%. In contrast, June boasts much warmer conditions with minimum temperatures of 10°C (49°F) and maximums reaching up to 35°C (96°F), averaging 17°C (63°F). This summer month experiences very little rain, with only 2 mm (0.1 inches) of precipitation and no rainy days, leading to a more comfortable humidity of 64%. For a deeper look into June's climate, you can check Palo Alto weather in June.
In December, the weather is significantly cooler, with temperatures ranging from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), and an average temperature of 11°C (52°F). This month also sees considerable rainfall, with 88 mm (3.5 in) of precipitation over about nine days, resulting in a high humidity level of 80%. In contrast, July offers a warmer and drier climate, with temperatures ranging from a minimum of 11°C (53°F) to a maximum of 29°C (84°F) and an average of 17°C (63°F). Remarkably, July experiences no rainfall at all, leading to a lower humidity of 58%. For more detailed information, you can check out Palo Alto weather in July.
December and August present stark contrasts in weather. In December, temperatures range from a minimum of 3°C (37°F) to a maximum of 22°C (72°F), with an average temperature of 11°C (52°F). The month is characterized by significant precipitation, averaging 88 mm (3.5 in) over about 9 days, along with a high humidity level of 80%. In contrast, August boasts much warmer temperatures, with a minimum of 12°C (54°F) and a maximum reaching up to 35°C (96°F), resulting in an average of 18°C (65°F). Notably, August experiences no precipitation, with humidity levels at a much more comfortable 54%. For more information on the summer weather patterns, check Palo Alto weather in August.
In comparison to December, September typically offers warmer temperatures, with a minimum of 10°C (50°F) and an average of 18°C (66°F), peaking at a sweltering 39°C (103°F). In sharp contrast, December sees cooler conditions, with temperatures ranging from a minimum of 3°C (37°F) to a maximum of 22°C (72°F) and an average of 11°C (52°F). September is also characterized by significantly lower precipitation, receiving only 2 mm (0.1 in) across the month, while December is noticeably wetter, with 88 mm (3.5 in) of rainfall on about 9 days, coupled with higher humidity levels at 80% compared to September's 55%. For more specific details, check out Palo Alto weather in September.
In comparing the weather of December and October, we see notable differences in temperature and precipitation. December, with a minimum temperature of 3°C (37°F) and an average of 11°C (52°F), is generally cooler than October, which boasts a higher minimum of 7°C (45°F) and an average temperature of 17°C (63°F). Additionally, October can reach maximum temperatures of 33°C (92°F), significantly warmer than December's maximum of 22°C (72°F). Precipitation levels also differ markedly; December experiences 88 mm (3.5 in) of rain over about 9 days, while October is much drier, with only 24 mm (0.9 in) across just 1 day. Humidity levels are also higher in December at 80%, compared to October's 62%. For a more detailed view of October's weather, you can visit Palo Alto weather in October.
In comparing the weather of December and November, we see some notable differences. December experiences slightly cooler temperatures, with a minimum of 3°C (37°F) and an average high of 22°C (72°F), while November is warmer, featuring a minimum of 4°C (39°F) and an average maximum of 27°C (80°F). Additionally, December has more precipitation, totaling 88 mm (3.5 in) across 9 days, compared to November's 47 mm (1.9 in) over just 5 days. Both months have comparable humidity levels, with December at 80% and November at 78%. For more details on November weather specifics, you can check Palo Alto weather in November.
As December rolls into Palo Alto, the weather brings a refreshing change compared to earlier months. With milder temperatures averaging around 11°C (52°F), residents experience cooler days and chillier nights, setting a cozy ambiance reminiscent of winter. The increase in humidity at 80% coupled with 88 mm of rain over nine days adds a distinctively damp feel to the season, contrasting sharply with the drier summer months. This blend of cool temperatures and an uptick in wet days invites locals to don their favorite seasonal attire and embrace the festive spirit. For more details on the annual weather patterns, visit Palo Alto Climate.