Last updated: February 24, 2025
In December, San Diego experiences mild and pleasant weather, characterized by an average temperature of 15°C (59°F), with maximums reaching up to 24°C (76°F) and minimums dipping to 8°C (47°F). Visitors can expect some occasional rainfall, with a total precipitation amount of 60 mm (2.4 in) spread over about 5 days. The city enjoys a relatively high humidity level of 74%, creating a refreshing atmosphere that complements its stunning coastal scenery. December in San Diego is a delightful time, balancing warmth and the charm of the holiday season.
In December, San Diego experiences a moderate climate that showcases the beauty of winter in Southern California. With minimum temperatures around 8°C (47°F) and average highs reaching 24°C (76°F), the month offers comfortable days perfect for outdoor activities. The transition from the cooler temperatures of November, where lows are slightly higher at 10°C (51°F), highlights a trend of mild winter weather that characterizes the region. This month typically sees a pleasant mix of sunny and cooler days, making it an ideal time for both locals and visitors to revel in the vibrant atmosphere of San Diego while enjoying the outdoors.
In December, San Diego experiences a noticeable uptick in precipitation, with 60 mm (2.4 in) of rain recorded over 5 days. This marks a significant increase compared to the preceding months, setting December apart as the wettest month of the year. The rainfall serves as a welcome shift from the arid summer, where barely any rain falls from June to August, reflecting the region's typically dry climate. As the year wraps up, this increase in moisture not only rejuvenates the environment but also hints at the seasonal transition from summer drought to the wetter winter months, making December a vital period for replenishing local ecosystems and water reserves.
As December arrives in San Diego, the humidity levels reflect a noticeable shift from the drier summer months. With humidity at 74%, this increase signals a return to more moisture-laden air, reminiscent of the higher levels seen at the beginning of the year. The trend clearly depicts a gradual rise, starting from the low of 42% in August, followed by a steady climb through the fall months, peaking just before winter. As temperatures drop and winter settles in, the city's humidity levels linger closer to the averages of early winter, creating a cozy ambiance perfect for the holiday season.
In December, San Diego experiences a UV Index of 4, classified as a moderate exposure category, with a burn time of 30 minutes. This marks a gentle decline from the extreme levels seen during the summer months, where the UV Index peaked at 11 in May, June, and July, requiring only 10 minutes for unprotected skin to burn. The transition into winter brings a gradual decrease in UV intensity, with February and March seeing higher values of 6 and 8, respectively. Despite the cooler season, those enjoying sunny outings should remain vigilant, as UV radiation can still pose a risk. For more detailed information on UV levels throughout the year, check out San Diego UV Index.
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In December, San Diego enjoys a milder climate as winter sets in, bringing an average of 231 hours of sunshine—a notable decline from the peak of 376 hours in the height of summer. This trend showcases a rhythmic ebb and flow of light throughout the year, where sunny days flourish from April to July. Interestingly, as the year unfolds, sunshine hours drop gradually, revealing a cozy transition into the colder months. Still, December's sunlight offers a comforting glow, inviting visitors to experience the city's vibrant outdoor scene even as the days grow shorter. Whether it's a leisurely stroll along the beach or enjoying holiday festivities, San Diego's December sun continues to charm.
In December, San Diego experiences a notable decline in sunny weather, with the chance of sunshine dropping to 47%. This marks a significant reduction compared to the earlier months of the year, illustrating a trend where the likelihood of clear skies steadily decreases as winter approaches. Interestingly, while December's chance of sunshine is lower, it aligns closely with May and June, suggesting a somewhat unpredictable climate as the holiday season rolls in. Overall, those dreaming of sunny beaches during this time may want to keep an eye on the forecast, as December tends to be cooler and cloudier than the vibrant, sunlit months preceding it.
In December, San Diego experiences 10 hours of daylight, mirroring the shorter days of January and November. This seasonal shift marks the transition into winter, where daylight gradually diminishes from the summer peak of 14 hours in June and July. As the year progresses from February's 11 hours to December's 10 hours, daylight hours ebb, illustrating a clear pattern of increasing brightness in spring and summer, with a gentle retreat as fall and winter set in. Despite the decrease, San Diego's mild climate coupled with its consistent daylight duration makes it an inviting destination year-round, allowing residents and visitors alike to embrace the beauty of each season.
In December, San Diego experiences a refreshing breeze with an average wind speed of 3.2 m/s (7 mph), maintaining a vibrant feel as the year concludes. This figure marks a notable rise from the wind speeds seen in November, which sank to a gentle 2.4 m/s (5 mph), signaling the onset of the winter season. December's winds are reminiscent of the spring months, such as March, where the average reached 3.4 m/s (8 mph), suggesting a consistent pattern of slightly higher winds as the year winds down. Overall, while the coastal city often enjoys mild breezes throughout the year, December stands out with a refreshing influx, perfect for outdoor celebrations and invigorating walks along the beach.
The weather in San Diego 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 San Diego and find detailed weather information for every month.
In comparing the weather between December and January, both months exhibit mild temperatures, with December experiencing an average of 15°C (59°F) and January slightly cooler at 14°C (58°F). The maximum temperatures remain relatively similar, with January reaching a peak of 25°C (77°F), just slightly above December's 24°C (76°F). Precipitation levels in January are lower at 45 mm (1.8 in) compared to December's 60 mm (2.4 in), although both months see rain on approximately five days. Humidity levels are also similar, with December at 74% and January slightly drier at 72%. For a more detailed look, you can learn about San Diego weather in January.
In December, temperatures range from a minimum of 8°C (47°F) to a maximum of 24°C (76°F), with an average temperature of 15°C (59°F). The month sees about 60 mm (2.4 in) of precipitation over 5 days, and humidity levels are around 74%. In contrast, February experiences slightly cooler temperatures, with a minimum of 7°C (45°F) and a maximum of 26°C (79°F), averaging 14°C (57°F). This month has just a bit less precipitation at 55 mm (2.2 in), spread over 6 days, while humidity rises slightly to 77%. For more detailed information, visit San Diego weather in February.
In December, temperatures in the area typically range from a minimum of 8°C (47°F) to a maximum of 24°C (76°F), with an average of 15°C (59°F). The month sees around 60 mm (2.4 in) of precipitation over approximately 5 days, contributing to a relatively high humidity level of 74%. In contrast, March has similar minimum temperatures but slightly warmer maximums, reaching up to 26°C (80°F), with the same average of 15°C (59°F). Precipitation in March is lower, totaling 38 mm (1.5 in) spread across 8 days, resulting in a humidity level of 67%. For more insights on March weather, you can check San Diego weather in March.
In December, the weather is generally mild with temperatures ranging from a minimum of 8°C (47°F) to a maximum of 24°C (76°F), averaging around 15°C (59°F). It tends to be quite humid at 74%, with about 60 mm (2.4 in) of precipitation occurring over 5 days. In contrast, April experiences slightly warmer conditions, with temperatures ranging from a minimum of 11°C (53°F) to a maximum of 29°C (84°F), and an average of 16°C (61°F). This month also sees significantly less rainfall, with only 20 mm (0.8 in) falling over just 2 days and humidity dropping to 56%. For more detailed information about the weather in April, you can check San Diego weather in April.
In comparing the weather of December and May, December presents a cooler climate with temperatures ranging from a minimum of 8°C (47°F) to a maximum of 24°C (76°F), while May shows a slightly warmer range with minimum temperatures of 12°C (54°F) and maximums reaching 25°C (78°F). Precipitation is more frequent in December, with 60 mm (2.4 in) of rain over 5 days, compared to May's milder 16 mm (0.6 in) of precipitation over just 4 days. Additionally, December exhibits higher humidity levels at 74%, while May enjoys a more comfortable 46% humidity. For more detailed information, you can check out San Diego weather in May.
In December, temperatures in San Diego range from a minimum of 8°C (47°F) to a maximum of 24°C (76°F), with an average of 15°C (59°F). The month sees about 60 mm (2.4 in) of precipitation over approximately 5 days, contributing to a higher humidity of 74%. In contrast, June offers warmer temperatures, with a minimum of 14°C (58°F) and a maximum reaching 29°C (84°F), averaging around 18°C (65°F). This month is characterized by significantly lower precipitation, measuring just 2 mm (0.1 in) with no rainy days, and a decreased humidity level of 48%. For more specifics on the weather during this time, you can check out San Diego weather in June.
December and July present strikingly different weather patterns. In December, temperatures range from a minimum of 8°C (47°F) to a maximum of 24°C (76°F), with an average of 15°C (59°F). The month receives 60 mm (2.4 in) of precipitation spread over about five days, contributing to a relatively high humidity level of 74%. In contrast, July offers warmer temperatures, with a minimum of 16°C (62°F), an average of 21°C (69°F), and a maximum of 29°C (85°F). Notably, July experiences minimal rainfall, with only 1 mm (0.1 in) recorded over the month and no rainy days, resulting in a much lower humidity of 46%. For more detailed insights, check out San Diego weather in July.
December and August present quite contrasting weather conditions. In December, temperatures range from a mild minimum of 8°C (47°F) to a comfortable maximum of 24°C (76°F), with an average of 15°C (59°F). This month is characterized by greater humidity at 74% and more precipitation, totaling 60 mm (2.4 in) over approximately 5 days. In stark contrast, August boasts warmer temperatures with a minimum of 17°C (63°F) and a maximum of 29°C (84°F), averaging 21°C (71°F). Notably, August experiences very little precipitation, with only 1 mm (0.0 in) recorded over the month and a significantly lower humidity level of 42%. For further details, you can explore more about San Diego weather in August.
When comparing the weather in December and September, noticeable differences emerge. December experiences milder temperatures, ranging from a minimum of 8°C (47°F) to a maximum of 24°C (76°F), with an average of 15°C (59°F). In contrast, September is warmer, with minimums around 17°C (62°F) and maximums reaching up to 31°C (88°F), resulting in a more comfortable average of 21°C (70°F). Additionally, December sees more precipitation, with about 60 mm (2.4 in) over 5 days, whereas September enjoys a dry spell with only 3 mm (0.1 in) of rain and no recorded precipitation days. The humidity levels also reflect this seasonal shift, with December at 74% compared to September's more pleasant 52%. For more detailed information on the weather patterns, visit San Diego weather in September.
In comparing December and October weather, December tends to be cooler with a minimum temperature of 8°C (47°F) and an average of 15°C (59°F), whereas October enjoys milder temperatures, ranging from a minimum of 13°C (55°F) to an average of 20°C (68°F). October also sees higher maximum temperatures peaking at 32°C (90°F), while December maxes out at 24°C (76°F). Additionally, precipitation is more frequent in December, occurring on about 5 days with a total of 60 mm (2.4 in), compared to October's lighter rainfall of just 13 mm (0.5 in) over 2 days. The humidity is higher in December at 74%, while October remains more comfortable at 58%. For more detailed insights, check out San Diego weather in October.
In comparing the weather of December and November, December tends to be slightly cooler, with average temperatures ranging from a minimum of 8°C (47°F) to a maximum of 24°C (76°F). In contrast, November features warmer temperatures, peaking at a maximum of 27°C (81°F) and an average of 17°C (63°F). Additionally, December experiences more precipitation, totaling 60 mm (2.4 inches) over about five days, whereas November sees only 24 mm (0.9 inches) over just two days. Humidity levels are also higher in December at 74%, compared to 66% in November. For more detailed information about November weather, you can check San Diego weather in November.
As December ushers in the winter season, San Diego experiences a notable change in weather, presenting a refreshing contrast to the sun-soaked summer months. With a mild average temperature of around 15°C (59°F), the city remains comfortably cool, making outdoor activities enjoyable without the sweltering heat. However, frequent rain with about 60 mm (2.4 in) across five days adds a dash of unpredictability to the month, raising the humidity to a noticeable 74%. This combination of cooler temperatures and increased precipitation sets December apart, inviting residents and visitors alike to embrace the season while enjoying the unique charm of the city. For a deeper dive into the year-round weather patterns, explore San Diego Climate.