Last updated: April 22, 2025
December in San Diego, Mexico, offers a delightful blend of mild temperatures and refreshing coastal breezes. With maximum temperatures reaching 29°C (84°F) and an average of 15°C (59°F), the climate is pleasantly warm, perfect for outdoor activities. The drop to a minimum of 1°C (34°F) during the nights adds a crisp touch to the winter air. Rainfall is minimal, accumulating to just 4 mm (0.1 in) over approximately 1 day, while the humidity hovers around a comfortable 81%. Experience the charm of San Diego this December, where sunny skies and inviting weather create an ideal atmosphere for both relaxation and exploration.
In December, San Diego, Mexico, offers a delightful taste of winter warmth, with temperatures ranging from a chilly 1°C (34°F) at night to a balmy 29°C (84°F) during the day. This month's average temperature of 15°C (59°F) reflects a gradual decline from the warmer months, yet still allows for comfortable outdoor activities under the sun. As the year wraps up, visitors can enjoy pleasant afternoons reminiscent of early spring, while the evenings invite cozy gatherings as temperatures dip. Overall, December serves as a charming transitional period, smoothly blending the year’s end with the coolness of winter.
In San Diego, Mexico, December delivers a tranquil end to the wet season, with a modest precipitation of just 4 mm (0.1 in), falling on a single day. This trend reflects a significant shift from the preceding months, where heavy rains dominated, particularly from June to September, accumulating impressive totals of 156 mm (6.2 in) to 160 mm (6.3 in). As the year closes, the dry spell is further emphasized by the sharp decrease in rainy days, dropping to just one, similar to the earlier months of the year. This pattern not only showcases the region’s seasonal variations but also highlights its transition into a drier climate as it heads into winter.
In San Diego, Mexico, December showcases a terrain of 81% humidity, a level that lies just below the peak months of October and November. This pattern indicates a gradual decline from the dampness of autumn, where humidity levels reach an impressive high, maintaining a moist atmosphere ideal for lush landscapes. Notably, as the winter months progress, the humidity fluctuations between the hotter late summer months and cooler winter months become more pronounced. While December’s humidity is slightly lower than its predecessors, it still reflects a significant moisture retention characteristic of this coastal region. Overall, the trend suggests a synergistic relationship between seasonality and humidity, painting a picture of San Diego as a city that thrives on its balmy, yet varied, climate.
In December, San Diego, Mexico, experiences a UV Index of 8, categorized as very high, which means sun exposure can still lead to skin damage in as little as 15 minutes. Notably, this month marks a slight decrease from the extreme levels seen in the previous months, where the UV Index peaked at 15 in April and May. This trend confirms a gradual decline as the year comes to a close, offering a reprieve from the intense summer sun while still emphasizing the need for protection. For those planning to enjoy the outdoors, it’s important to stay vigilant about sun safety, even in winter. For more insights on UV levels throughout the year, check out the detailed San Diego UV Index.
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As winter settles in across much of the Northern Hemisphere, San Diego radiates with a delightful charm, boasting an impressive 288 hours of sunshine in December. This is a consistent continuation of the city's sun-filled persona, following a trend of ample daylight that begins with 235 hours in January and peaks during the vibrant spring months. Notably, average sunshine hours steadily increase from a modest 271 in February to 345 by May, showcasing the region's appeal as a sun-soaked paradise. Even as the year winds down, San Diego remains a haven of light, maintaining a remarkable level of brightness that invites both residents and visitors to bask in the warmth of December's glow.
San Diego, Mexico, experiences a delightful trend in sunny weather as the year winds down. In December, the chance of sunshine is a promising 73%, making it a favorable time for outdoor activities and beach outings. This likelihood follows a pattern where the winter months, particularly December, exhibit a notable increase in sun compared to the summer months, which see a drop to as low as 24%. As we transition from November's 65% chance of sun to December's warmer embrace of sunlight, visitors can expect pleasant weather that is perfect for enjoying the coastal beauty. Overall, December stands out as a prime month for sun seekers, bookended by the sunnier months of February and March.
In San Diego, Mexico, December brings a gentle decline in daylight, with just 10 hours of sunshine, marking the shortest days of the year. The daylight duration begins at 11 hours in January and February, gradually increases through the spring months of March and April to reach 12 hours in May. As summer approaches, the days peak at 13 hours between June and July, offering ample sunlight for outdoor adventures. However, as autumn sets in, daylight starts to wane again, returning to 11 hours in November before tapering off in December. This cyclical pattern of light serves as a reminder of the seasonal changes, allowing residents and visitors to plan for the sun's ebbs and flows throughout the year.
As December settles in San Diego, Mexico, the average wind speed gently drops to 1.9 m/s (4 mph), marking it as one of the calmest months of the year. This decline follows a slight uptick in April when winds breathed mildly at 2.9 m/s (7 mph). Throughout the year, wind patterns exhibit a fascinating ebb and flow; from January to April, there's a noticeable increase, peaking in April before gradually tapering off into the slower speeds that characterize the latter months. The consistent drop into December, coupled with the very subdued breezes of November, reflects the region’s tranquil winter climate, inviting locals and visitors alike to enjoy the scenic coastal beauty without the interference of blustery winds.
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 December, the weather features a minimum temperature of 1°C (34°F) and an average of 15°C (59°F), peaking at a maximum of 29°C (84°F). The month sees minimal precipitation of 4 mm (0.1 in) over just one day, coupled with a relatively high humidity level of 81%. In contrast, January offers slightly warmer minimum temperatures at 2°C (36°F), while the average and maximum temperatures remain unchanged. January also experiences the same precipitation amount of 4 mm (0.2 in) over one day, but with a lower humidity level of 74%. For more details, check out San Diego weather in January.
In December, the weather typically ranges from a minimum of 1°C (34°F) to a maximum of 29°C (84°F), with an average temperature of 15°C (59°F). Precipitation is minimal, with just 4 mm (0.1 in) expected over one day, and humidity levels are relatively high at 81%. In contrast, February brings slightly warmer temperatures, with a minimum of 4°C (40°F) and a maximum of 31°C (88°F), averaging around 17°C (64°F). Precipitation increases to 6 mm (0.2 in) over one day, and humidity drops significantly to 65%. For more details, you can check San Diego weather in February.
In December, the weather tends to be milder, with temperatures ranging from a minimum of 1°C (34°F) to a maximum of 29°C (84°F) and an average of 15°C (59°F). This month sees low precipitation levels, with just 4 mm (0.1 in) over the course of 1 day, and humidity levels are quite high at 81%. In contrast, March experiences warmer temperatures, with a minimum of 5°C (41°F) and a maximum of 33°C (92°F), averaging around 20°C (69°F). Precipitation slightly increases to 7 mm (0.3 in) over 2 days, but humidity drops to a more comfortable 58%. For a more detailed look at March weather, check out San Diego weather in March.
In December, the weather experiences milder temperatures with a minimum of 1°C (34°F) and an average of 15°C (59°F), while enjoying maximum highs of 29°C (84°F). The month sees minimal precipitation, averaging just 4 mm (0.1 in) over about one day of rain, coupled with higher humidity levels at 81%. In contrast, April offers a more pronounced warming trend, with temperatures ranging from a minimum of 8°C (46°F) to an average of 22°C (72°F) and peaks reaching up to 35°C (95°F). Notably, April experiences little to no rainfall, totaling just 3 mm (0.1 in) with no rainy days, and a decrease in humidity to 58%. For more insights into the weather specifically during April, check out San Diego weather in April.
When comparing the weather in December and May, significant differences emerge. December experiences milder temperatures, with a minimum of 1°C (34°F) and a pleasant average of 15°C (59°F), peaking at 29°C (84°F). In contrast, May brings much warmer conditions, with a minimum of 12°C (53°F) and an average of 23°C (74°F), reaching highs of 36°C (97°F). Additionally, December is relatively dry with only 4 mm (0.1 in) of precipitation over just one day, while May sees more rain, totaling 36 mm (1.4 in) across six days. Humidity levels are also higher in December at 81%, compared to May’s 67%. For more details, you can check San Diego weather in May.
When comparing the weather in December and June, we find significant differences in temperature and precipitation. December features a milder climate with temperatures ranging from a minimum of 1°C to a maximum of 29°C, boasting an average of 15°C. The month is relatively dry, with only 4 mm of precipitation over just one day and a humidity level of 81%. In contrast, June presents a much warmer environment, with temperatures starting at a low of 12°C and peaking at 36°C, averaging around 22°C. This month is characterized by substantial rainfall, receiving 156 mm over approximately 15 days, along with a slightly lower humidity of 76%. For a closer look at June weather patterns, you can visit San Diego weather in June.
The weather in December and July exhibits significant differences. In December, temperatures range from a cool 1°C (34°F) at night to a warm average of 15°C (59°F) during the day, peaking at 29°C (84°F). The month is relatively dry with only 4 mm (0.1 in) of precipitation over just 1 day, and humidity levels are high at 81%. In contrast, July brings warmer temperatures, with nighttime lows around 12°C (54°F) and daytime averages of 20°C (69°F), reaching a maximum of 31°C (89°F). July is also far wetter, recording 160 mm (6.3 in) of rainfall over approximately 20 days, alongside a lower humidity level of 67%. This stark contrast highlights the seasonal variations, making each month unique in its climate. For more details, check out San Diego weather in July.
December and August exhibit stark differences in weather patterns. December brings cooler temperatures with a minimum of 1°C (34°F) and an average high of 29°C (84°F), while August sees warmer conditions, ranging from a minimum of 12°C (54°F) to a maximum of 31°C (88°F). Precipitation is significantly lower in December, with only 4 mm (0.1 in) falling over just one day, compared to August's 145 mm (5.7 in) across 17 days. Additionally, December's humidity is higher at 81%, while August has a more moderate humidity level of 68%. For a comprehensive look at summer conditions, check out San Diego weather in August.
In comparing the weather between December and September, we see notable differences in temperature and precipitation. December experiences milder temperatures, with an average of 15°C (59°F) and only a slight chance of rain, receiving just 4 mm (0.1 in) of precipitation over the course of a single day. In contrast, September is generally warmer, boasting an average temperature of 20°C (68°F) and reaching highs of up to 31°C (88°F). However, it is significantly wetter, with a substantial 147 mm (5.8 in) of rainfall spread over 17 days. Both months share a consistent level of humidity at 81%, but the overall experience of weather in September is marked by increased moisture and warmth. For more specific insights, you can check San Diego weather in September.
In comparing the weather between December and October, we see notable differences. December experiences milder temperatures with a minimum of 1°C (34°F) and averages around 15°C (59°F), peaking at 29°C (84°F). In contrast, October is warmer, showcasing a minimum of 6°C (43°F) and an average of 19°C (67°F), with maximum temperatures reaching 31°C (89°F). Additionally, October is significantly wetter, receiving 48 mm (1.9 in) of precipitation over 8 days, compared to December's minimal 4 mm (0.1 in) over just one day. Despite the slight increase in humidity levels, from 81% in December to 83% in October, the overall weather is much more conducive to outdoor activities in October. For more detailed insights, check out San Diego weather in October.
In comparing December and November weather, December tends to be slightly cooler, with average temperatures ranging from a minimum of 1°C (34°F) to a maximum of 29°C (84°F), while November experiences slightly warmer temperatures with a minimum of 2°C (36°F) and a maximum of 30°C (87°F). Additionally, December is much drier, with only 4 mm (0.1 in) of precipitation over just 1 day, compared to November's 16 mm (0.6 in) over 2 days. Humidity levels remain relatively consistent, with December at 81% and November slightly higher at 84%. For a more detailed look at November’s conditions, you can visit San Diego weather in November.
In December, San Diego experiences a delightful shift in weather that sets it apart from the rest of the year. With average temperatures hovering around a comfortable 15°C (59°F), visitors can enjoy the mild climate without the sweltering heat typical of summer months. Unlike the sun-drenched days of July and August, December brings a refreshing respite, featuring only a slight chance of rain—just 1 day of precipitation contributing to a total of 4 mm (0.1 in). Humidity levels are higher at 81%, lending a crispness to the air that is invigorating for outdoor activities. For those seeking a pleasant winter getaway, December proves to be an ideal time to explore all that this coastal gem has to offer. Learn more about the nuances of weather throughout the year by checking out the complete San Diego Climate guide.