Last updated: February 24, 2025
In December, Pasadena experiences a diverse range of temperatures, with a maximum of 27°C (81°F) and a chilly minimum dipping to 1°C (33°F). The average temperature hovers around a mild 12°C (53°F), making it a pleasant time to enjoy the city's winter charm. While the month sees an accumulated precipitation of 77 mm (3.1 in) over 5 days, the humidity level remains a notable 76%, contributing to a crisp and refreshing atmosphere. December in Pasadena offers a unique blend of warmth and coolness, perfect for exploring the vibrant local culture amidst the scenic winter backdrop.
In Pasadena, December brings a refreshing chill as temperatures transition towards the cooler end of the year. With minimums hovering around 1°C (33°F) and averages settling at a comfortable 12°C (53°F), residents experience a delightful reprieve from the summer heat. The maximum temperatures peak at 27°C (81°F), showcasing a mild and pleasant climate ideal for outdoor festivities. This month not only captures the essence of winter but also hints at the approach of colder months ahead, as it neatly transitions from November's slightly warmer values, all while maintaining the city's characteristic warmth during the day. The trend reflects a gradual drop in temperature as the year winds down, making December in Pasadena a charming blend of cozy and inviting.
In Pasadena, December brings a refreshing change to the typically dry climate, contributing 77 mm (3.1 in) of precipitation over 5 days. This amount is notably higher than the minimal rainfall experienced during the summer months, highlighting a seasonal contrast. As the year draws to a close, December's rainfall levels are comparable to January's, yet they stand out against the much drier conditions of late spring and summer. With the holiday season often celebrated amid cooler, wetter weather, these December showers provide a much-needed boost to the region’s water supply, while also enhancing the vibrant hues of the surrounding landscapes. This pattern reflects Pasadena's transition into winter, where enhanced moisture sets the stage for a greener start to the new year.
In Pasadena, December brings a noticeable uptick in humidity, averaging 76%, a slight increase from the previous month. This rise is part of a larger trend as the city transitions from the drier summer months, where humidity levels dipped to a low of 39% in August. As the year progresses, a gradual increase in moisture is observable, with the winter months consistently offering higher humidity compared to the summer. December's humidity reflects a return to more moderate values, reminiscent of the early winter months, making it feel relatively comfortable as the region heads into the heart of the chilly season. Overall, these fluctuations highlight Pasadena's shift from the dry heat of summer to the wetter embrace of winter, creating a dynamic climate experience throughout the year.
In December, Pasadena experiences a UV Index of 4, which falls into the moderate exposure category, allowing for a burn time of approximately 30 minutes under direct sunlight. As the year progresses, a noticeable trend emerges: from low levels in January, the UV Index steadily rises to a staggering 12 in July, indicating extreme sun exposure. Following a peak in mid-summer, the index gradually descends through the fall and winter months, culminating in December's more manageable levels. Overall, while UV intensity fluctuates throughout the year, December offers a reprieve, making it a great time for outdoor activities with proper sun protection. For detailed information on daily UV levels and safety precautions, visit Pasadena UV Index.
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As December arrives in Pasadena, the sun remains a steadfast companion, showering the city with 222 hours of sunlight. While this marks a decline from the sun-soaked peak of 381 hours in July, it’s part of a predictable trend where daylight gradually tapers off as winter approaches. Throughout the year, Pasadena basks in generous sunlight, particularly in the vibrant summer months, with totals soaring above 350 hours from May to August. Interestingly, December’s sunshine, while less than in the months prior, still offers a bright end to the year, maintaining the region's reputation for pleasant winter weather. This steady shift from the bright warmth of summer to the cooler winter days highlights Pasadena's alluring resilience in the face of the changing seasons.
While Pasadena basks in warm sunshine for most of the year, December marks a noticeable shift in weather patterns. The likelihood of sunny days dips to 51%, contrasting sharply with the higher percentages seen in preceding months. This decline reflects a transition into the winter season, where clouds and rain make more frequent appearances. Notably, the sun shines most consistently from late spring through early autumn, peaking at 85% in September. As December unfolds, residents may find themselves trading beach days for cozy afternoons indoors, but the allure of Pasadena's mild winter remains a cherished aspect of its climate.
As December settles in Pasadena, the city experiences its shortest daylight duration of the year, offering just 9 hours of sunlight each day. This marks a notable decline from the longer days of summer, where June and July enjoyed a generous 14 hours each. As the year progresses from the vibrant spring months, which enjoy around 13 hours in April and May, daylight gradually recedes, dipping to 10 hours in November. This trend illustrates the seasonal rhythm of light and darkness, highlighting how winter’s chill envelops the charming city. Embracing the transitional nature of December, residents turn to brighter indoor activities, cherishing the fleeting hours of daylight as they prepare for the longer days ahead with the arrival of spring.
In Pasadena, the December wind mirrors the tranquil patterns seen throughout the year, with an average speed of 2.0 m/s (4 mph). As the colder months roll in, the winds remain gentle, consistent with a gradual decline observed from January onward. While January boasts the highest winds of the year at 2.4 m/s (5 mph), December's calm breezes reflect a seasonal shift, contributing to the mild winter atmosphere. Overall, the data reveals a distinct trend of decreasing wind speeds as the year progresses, creating inviting conditions for enjoying Pasadena's picturesque winter landscape.
The weather in Pasadena 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 Pasadena and find detailed weather information for every month.
In comparing the weather between December and January, we see notably mild conditions prevailing in both months. December features a minimum temperature of 1°C (33°F) and a maximum of 27°C (81°F), while January is slightly cooler with a minimum of 0°C (32°F) and a maximum of 29°C (84°F). Both months experience similar average temperatures, holding steady at 12°C (53°F), and have comparable precipitation levels, with December receiving 77 mm (3.1 in) and January 75 mm (3.0 in), typically falling over five days each month. Humidity levels rise slightly from December's 76% to January's 78%, contributing to a consistent but slightly more damp atmosphere. For a detailed look at specific conditions, you can visit Pasadena weather in January.
December and February in Pasadena present mild temperatures, with averages around 12°C (53°F) in both months. December experiences slightly warmer maximum temperatures, reaching up to 27°C (81°F), compared to February's peak of 28°C (83°F). Precipitation is a bit higher in December, totaling 77 mm (3.1 in) over approximately five days, whereas February sees a bit less with 65 mm (2.6 in) across six days. Humidity levels rise in February, reaching 82%, compared to December's 76%. For more detailed information on February weather, check out Pasadena weather in February.
In December, the weather tends to be cooler with average temperatures ranging from a minimum of 1°C (33°F) to a maximum of 27°C (81°F), accompanied by 77 mm (3.1 in) of precipitation over about 5 days and humidity levels around 76%. In contrast, March experiences slightly warmer conditions, with average temperatures soaring from a minimum of 1°C (34°F) to a maximum of 30°C (86°F). The precipitation increases to 85 mm (3.4 in), spread over 10 days, while the humidity remains relatively stable at 75%. For more detailed information, you can check Pasadena weather in March.
December's weather presents a cooler experience, with temperatures ranging from a minimum of 1°C (33°F) to a maximum of 27°C (81°F), and an average of 12°C (53°F). The month sees significant precipitation, accumulating to 77 mm (3.1 in) over about 5 days, and boasts a relatively high humidity level of 76%. In contrast, April brings milder temperatures with a minimum of 6°C (43°F) and a maximum of 34°C (94°F), averaging 17°C (62°F). The rainfall is considerably less, with only 22 mm (0.9 in) over 2 days, and the humidity drops to 68%. For more detailed insights, check out Pasadena weather in April.
In December, the weather features a cooler climate with temperatures ranging from a minimum of 1°C (33°F) to a maximum of 27°C (81°F), along with an average of 12°C (53°F). The month sees higher precipitation levels at 77 mm (3.1 inches) over about five days, accompanied by a humidity level of 76%. In contrast, May offers a noticeably warmer experience with temperatures ranging from a minimum of 6°C (43°F) to a maximum of 34°C (94°F) and an average of 18°C (64°F). Rainfall is significantly lower at just 16 mm (0.6 inches) occurring over three days, and humidity drops to 57%. For more details, check out Pasadena weather in May.
December weather features a wide range of temperatures, with minimums dipping to around 1°C (33°F) and maximums reaching up to 27°C (81°F). This month experiences moderate precipitation of 77 mm (3.1 in) over about 5 days, resulting in a high humidity level of 76%. In contrast, June boasts a significantly warmer climate, with minimum temperatures starting at 11°C (51°F) and soaring to an impressive maximum of 40°C (105°F). June is virtually dry, receiving only 1 mm (0.1 in) of precipitation throughout the month, and has a much lower humidity level of 52%. For more specific details on June weather, you can visit Pasadena weather in June.
December and July present stark contrasts in weather. In December, temperatures range from a low of 1°C (33°F) to a high of 27°C (81°F), with an average temperature of 12°C (53°F). The month also sees about 77 mm (3.1 in) of precipitation over five days and humidity levels around 76%. In contrast, July boasts much warmer conditions, with a minimum temperature of 13°C (57°F) and soaring highs that can reach 43°C (109°F), averaging 25°C (77°F). This summer month is remarkably drier, featuring only 2 mm (0.1 in) of precipitation and no rainy days, while humidity drops to 46%. For more details, check out Pasadena weather in July.
When comparing December and August weather, the temperature variation is quite notable. December experiences cooler temperatures, with a minimum of 1°C (33°F) and an average of 12°C (53°F), peaking at a maximum of 27°C (81°F). In contrast, August boasts much warmer conditions, with temperatures ranging from a minimum of 15°C (59°F) to a maximum of 40°C (105°F), averaging around 25°C (78°F). Additionally, December is characterized by higher humidity at 76% and more precipitation, with an average of 77 mm (3.1 in) over five days. Conversely, August typically enjoys dry weather, with only 2 mm (0.1 in) of precipitation over the month and significantly lower humidity at 39%. For more detailed insights on the specific weather of August, you can refer to Pasadena weather in August.
The weather in December presents a stark contrast to that of September. In December, temperatures range from a chilly minimum of 1°C (33°F) to a more moderate maximum of 27°C (81°F), with an average temperature of 12°C (53°F). This month also sees more precipitation, with about 77 mm (3.1 in) over five days and a high humidity level of 76%. In comparison, September boasts significantly warmer temperatures, with a minimum of 10°C (51°F) and an impressive maximum of 44°C (112°F), leading to an average of 23°C (74°F). Interestingly, September enjoys a much drier climate, recording only 4 mm (0.1 in) of rainfall over zero days and a lower humidity of 48%. For more details on September's weather patterns, you can check out Pasadena weather in September.
In comparing the weather between December and October, October typically boasts warmer temperatures, with a minimum of 6°C (44°F) and an average of 20°C (68°F), reaching highs of up to 38°C (101°F). In stark contrast, December experiences much cooler temperatures, with a minimum of 1°C (33°F) and an average of 12°C (53°F), though it can peak at 27°C (81°F). Additionally, October is notably drier, recording only 9 mm (0.4 in) of precipitation over just 1 day, while December sees increased rainfall of 77 mm (3.1 in) across 5 days and higher humidity levels at 76%. For a detailed look at October weather specifics, you can visit Pasadena weather in October.
In comparing the weather of December and November, December tends to be cooler with a minimum temperature of 1°C (33°F) and an average of 12°C (53°F), while November features slightly milder temperatures, with a minimum of 2°C (37°F) and an average of 16°C (61°F). The maximum temperatures in November also reach up to 31°C (89°F), compared to December's peak of 27°C (81°F). Precipitation is more frequent in December, accumulating to 77 mm (3.1 in) over 5 days, whereas November has a much drier climate with only 24 mm (0.9 in) over 2 days. Humidity levels are slightly higher in December at 76%, compared to November's 72%. For more details on November's climate, you can check out Pasadena weather in November.
As December unfolds in Pasadena, the weather presents a refreshing contrast to the warmer months. With mild temperatures averaging around 12°C (53°F), the cool atmosphere invites a cozy vibe—ideal for enjoying the holiday season. Unlike the drier summer months, December brings a bit of moisture, with 77 mm (3.1 in) of precipitation over about 5 days, often accompanied by a humidity level of 76% that softens the crisp air. This blend of cooler temperatures and occasional rain makes December a unique transition into winter in Pasadena, offering a delightful change of pace. For more insights into what to expect throughout the year, visit Pasadena Climate.