Last updated: February 24, 2025
December in San Luis Obispo presents a mild climate characterized by a pleasant maximum temperature of 23°C (74°F) and an average of 12°C (54°F). With a minimum temperature dipping to 5°C (42°F), the month brings a cool, refreshing atmosphere. Precipitation is moderate, totaling 76 mm (3.0 in) over 6 days, contributing to the region's lush landscapes and vibrant flora. Humidity levels hover around 76%, creating a crisp, invigorating feel in the air. Overall, December offers a charming blend of warmth and coolness, ideal for enjoying outdoor activities in this picturesque coastal town.
In San Luis Obispo, December ushers in the final stretch of the year with mild temperatures that reflect the typical coastal climate of the region. The average temperature settles at a comfortable 12°C (54°F), with daily highs reaching a pleasant 23°C (74°F). As the month progresses, you can expect minimum temperatures to dip only slightly to around 5°C (42°F), providing a gentle chill during the evenings. Compared to previous months, December exhibits a subtle coolness yet maintains a balance that invites outdoor activities and festive cheer. This consistency in temperatures, alongside the stunning winter sunsets, makes December in San Luis Obispo both inviting and invigorating, perfect for cozy gatherings or leisurely strolls through the charming streets.
In December, San Luis Obispo experiences a notable uptick in precipitation, with approximately 76 mm (3.0 in) of rain, falling on about 6 days. This marks a significant increase from the drier summer months, where the total rainfall barely registered at just 1 mm in both June and July. As the year wraps up, December's rainfall is reminiscent of the winter pattern seen earlier in the season, aligning more closely with the wetter months of January and February. While November brings a modest 32 mm, December's accumulation underscores a shift towards the more typical California winter, offering a refreshing contrast to the arid conditions of midsummer. Overall, the wet December sets a hopeful tone for the coming year, recharging local ecosystems and replenishing water sources after an extended dry spell.
In San Luis Obispo, December ushers in a slight rise in humidity, with levels reaching 76%. This increase marks a seasonal trend, as the city experiences its highest humidity earlier in the year, peaking at 83% in February before gradually declining through the warmer months. From July onward, humidity levels remain relatively stable, hovering between 70% and 76%. As the year wraps up, December reflects a return to slightly higher moisture levels, suggesting a transition into the wetter months ahead. Overall, this fluctuation showcases San Luis Obispo's characteristic mild climate, balancing comfort with occasional bursts of humidity throughout the year.
In December, San Luis Obispo experiences a UV Index of 3, indicating a moderate exposure level with a burn time of approximately 30 minutes. This marks a noticeable drop from the extreme levels seen in the summer months, where the UV Index peaked at 12. As the year winds down, the region transitions through varying exposure categories, beginning with a robust 9 in April and gradually decreasing, ultimately reaching this more manageable figure in December. Such seasonal fluctuations highlight the importance of being vigilant about sun protection, even during the cooler months. For more detailed insights, visit San Luis Obispo UV Index.
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In December, San Luis Obispo enjoys a delightful blend of sunshine, basking in an average of 223 hours of radiant light. While this marks a gentle decline from the vibrant 368 hours of May and the peak of 383 hours in July, it still presents a cozy contrast to the cold winter months elsewhere. The overall trend reveals a gradual increase in daylight hours as the year unfolds, culminating in a golden summer before transitioning to the softer glow of winter. This notable December sunshine offers residents and visitors alike the perfect opportunity to relish the mild weather and festive atmosphere, making it a charming time to explore this beautiful Californian gem.
In December, San Luis Obispo experiences a notable dip in sunny weather, with only a 49% chance of sunshine gracing the landscape. This marks a decline from the more optimistic forecasts of late summer and early fall, where the chances hovered around 68%. The trend showcases a gradual decrease in sunshine as the year draws to a close, with the peak months of May (72%) and June (73%) shining brightly compared to December’s more subdued outlook. As the festive season sets in, residents and visitors alike might want to prepare for a greyer sky, embracing the cozy charm of winter in this picturesque coastal town.
In San Luis Obispo, December marks the season's transition into shorter days, where the daylight duration dips to just 9 hours. This decline is a continuation of the trend observed from November, which also offers a brief 10 hours of sunlight. Reflecting on the year, it's evident that daylight peaks in the vibrant months of May through July, showcasing an impressive 14 hours of natural light that fuels outdoor activities. As summer fades and autumn sets in, the daylight gradually decreases, reminding residents and visitors alike of the cyclical nature of the seasons. Thus, as December arrives, it gently ushers in longer nights, inviting cozy evenings and a festive atmosphere as the year draws to a close.
As the year winds down, December in San Luis Obispo brings a gentle increase in average wind speed to 3.1 m/s (7 mph), marking a subtle shift from the lighter breezes of summer. While the summer months of July and August experience their calmest gusts at around 2.1 m/s (5 mph), the transition into fall and then winter promotes a gradual uptick in wind activity. Notably, December's winds are somewhat reminiscent of the earlier months, such as January and November, where breezes hover around the same moderate speeds. This consistent yet mild wind contributes to a refreshing atmosphere, perfect for those looking to enjoy the scenic beauty of the Californian coast.
The weather in San Luis Obispo 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 Luis Obispo and find detailed weather information for every month.
December and January in San Luis Obispo exhibit similar average temperatures, with both months maintaining an average of 12°C (54°F) and highs of 23°C (74°F). However, January tends to be slightly cooler at night, with a minimum temperature of 4°C (40°F) compared to December's 5°C (42°F). While both months see precipitation on approximately six days, January experiences significantly more rainfall, totaling 110 mm (4.3 in) compared to December's 76 mm (3.0 in). Additionally, January has a higher humidity level of 80%, making it feel a bit wetter than December's 76% humidity. For more detailed information, you can check San Luis Obispo weather in January.
In December, the weather features a mild climate with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 23°C (74°F), resulting in an average temperature of 12°C (54°F). The month experiences 76 mm (3.0 in) of precipitation over approximately 6 days, accompanied by a humidity level of 76%.
February presents similar average temperatures, maintaining 12°C (54°F) as well, but with a slightly lower minimum of 4°C (39°F) and a higher maximum of 25°C (77°F). The precipitation increases slightly to 80 mm (3.2 in), also spread over 6 days, accompanied by a higher humidity of 83%.
For a detailed look at February conditions, you can visit San Luis Obispo weather in February.
When comparing the weather in December and March, both months exhibit mild temperatures, but March tends to be slightly warmer. In December, temperatures range from a minimum of 5°C (42°F) to a maximum of 23°C (74°F), averaging around 12°C (54°F). In contrast, March sees a minimum of 5°C (41°F) and a maximum of 24°C (76°F), with an average temperature of 13°C (55°F).
Precipitation is slightly higher in March, totaling 84 mm (3.3 in) over approximately 9 days, compared to December's 76 mm (3.0 in) over 6 days. The humidity also increases slightly from December’s 76% to March’s 80%. For more detailed insights, check out the San Luis Obispo weather in March.
December and April in San Luis Obispo exhibit distinct weather patterns. December tends to be cooler, with average temperatures ranging from a minimum of 5°C (42°F) to a maximum of 23°C (74°F), while April shows slightly warmer averages, with temperatures ranging from 7°C (44°F) to 26°C (80°F). Precipitation is notably higher in December, with 76 mm (3.0 in) over about six days, compared to a more moderate 23 mm (0.9 in) across three days in April. Despite the differences, both months share the same humidity level of 76%. For a detailed look at April's climate, visit San Luis Obispo weather in April.
In December, the weather is generally cooler, with average temperatures ranging from a chilly 5°C (42°F) at night to a mild 23°C (74°F) during the day. This month sees more rainfall, averaging 76 mm (3.0 in) over about 6 days, contributing to a higher humidity level of 76%. In contrast, May brings warmer temperatures, with night lows around 8°C (47°F) and daytime highs reaching 25°C (77°F). The precipitation drops significantly to only 12 mm (0.5 in) over just 2 days, while humidity remains relatively stable at 75%. For more details on the typical weather conditions in May, you can check San Luis Obispo weather in May.
In December, the weather is generally cooler, with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 23°C (74°F), and an average of 12°C (54°F). This month also sees a fair amount of rain, with precipitation totaling 76 mm (3.0 in) over about 6 days, and humidity levels are relatively high at 76%. In contrast, June offers warmer conditions, with temperatures ranging from a minimum of 11°C (51°F) to a maximum of 31°C (88°F), and an average of 16°C (62°F). Notably, June is much drier, receiving only 1 mm (0.0 in) of precipitation across 0 days, accompanied by a slightly lower humidity level of 74%. For more details, you can check San Luis Obispo weather in June.
December and July present strikingly different weather patterns. In December, temperatures range from a minimum of 5°C (42°F) to a maximum of 23°C (74°F), with an average of 12°C (54°F). The month tends to be wetter, receiving 76 mm (3.0 in) of precipitation over six days, accompanied by a humidity level of 76%. In contrast, July boasts warmer temperatures, ranging from a minimum of 12°C (55°F) to a peak of 31°C (89°F), with an average temperature of 18°C (64°F). Notably, July is much drier, with only 1 mm (0.0 in) of precipitation across the entire month and no rainy days, while humidity remains relatively similar at 75%. For more details, you can explore San Luis Obispo weather in July.
In December, the weather is generally cooler with minimum temperatures dropping to around 5°C (42°F) and an average of 12°C (54°F), peaking at 23°C (74°F). The month sees a total of 76 mm (3.0 in) of precipitation spread over six days, contributing to a relatively high humidity of 76%. In contrast, August offers much warmer conditions, with minimum temperatures starting at 13°C (55°F) and averaging 18°C (65°F), reaching highs of 31°C (88°F). Precipitation in August is minimal, with just 1 mm (0.0 in) recorded on no rainy days, and humidity slightly lower at 72%. For more specific details about August weather, you can check San Luis Obispo weather in August.
December and September showcase contrasting weather patterns. In December, temperatures range from a minimum of 5°C (42°F) to a maximum of 23°C (74°F), with an average of 12°C (54°F). This month experiences more precipitation, totaling 76 mm (3.0 in) over six days, coupled with a higher humidity level of 76%. In contrast, September boasts warmer temperatures, with nighttime lows around 11°C (53°F) and daytime highs reaching up to 35°C (95°F). This month sees minimal precipitation, with just 1 mm (0.0 in) and no rainy days, and a slightly lower humidity level of 70%. For a detailed view of September's climate, visit San Luis Obispo weather in September.
In comparing the weather between December and October, December tends to be cooler, with average temperatures ranging from a minimum of 5°C (42°F) to a maximum of 23°C (74°F), while October offers milder conditions, with an average low of 9°C (49°F) and a high of 33°C (92°F). Additionally, December experiences higher humidity levels at 76% compared to October's 70%, and significantly more precipitation, with 76 mm (3.0 in) over six days, unlike October, which sees virtually no rainfall at just 10 mm (0.4 in) over zero days. For more specific details on October's climate, you can check San Luis Obispo weather in October.
When comparing the weather in December to November, we see a noticeable shift in temperature and precipitation patterns. December's minimum temperature averages around 5°C (42°F), slightly cooler than November's 6°C (42°F), but the average maximum temperature in December is 23°C (74°F), which is a bit lower than November's maximum of 26°C (79°F). Precipitation also increases significantly in December, with 76 mm (3.0 in) over 6 days, compared to November's 32 mm (1.2 in) across just 3 days. Humidity remains relatively stable, averaging 76% in December compared to 74% in November. For more detailed information, check out San Luis Obispo weather in November.
In December, San Luis Obispo experiences a delightful shift in weather compared to the warmer months, inviting visitors to embrace the cozy charm of the season. With average temperatures hovering around a comfortable 12°C (54°F) and a maximum reaching 23°C (74°F), the days are pleasant yet mild. However, the month also brings a noticeable increase in humidity and occasional rainfall, with 76 mm of precipitation spread over about 6 days. This creates a refreshing atmosphere perfect for those looking to enjoy the beauty of the outdoors while still feeling the festive spirit. Discover more about the climate nuances and prepare for your visit by checking out San Luis Obispo Climate.