December Weather in Oceanside, United States

Last updated: February 24, 2025

December in Oceanside, United States, unveils a diverse weather palette, with temperatures peaking at a pleasant 26°C (78°F) and cooling down to a minimum of 7°C (46°F). The average temperature settles at a comfortable 15°C (59°F), making it a mild month for outdoor activities. Despite its mildness, December sees about 63 mm (2.5 in) of rainfall across 5 days, contributing to a humid environment with an average humidity level of 71%. This blend of temperature and precipitation creates an inviting atmosphere for both locals and visitors to enjoy the coastal charm of Oceanside.

December Temperature in Oceanside

In December, Oceanside, United States experiences a delightful shift as temperatures begin to cool, marking the transition to winter. The month typically sees minimums around 7°C (46°F), with an average temperature of 15°C (59°F) that provides a comfortable ambiance for outdoor activities. Daytime highs can reach up to 26°C (78°F), allowing for pleasant afternoons that are perfect for exploration along the picturesque coastline. As the year winds down, the weather reflects a trend of decreasing temperatures from the warmer months, yet remains inviting enough for locals and visitors alike to enjoy the beauty of Oceanside.

December Weather in Oceanside: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Oceanside, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec585759616266717271696459
Data source: Temperature data for Oceanside generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Oceanside

In Oceanside, United States, December emerges as a notable month for precipitation, with an average of 63 mm (2.5 in) falling over five days. This increase marks a significant rise compared to the drier summer months, which see almost negligible rainfall, such as June and August, recording just 3 mm (0.1 in) and 1 mm (0.0 in) respectively. As the year draws to a close, December experiences a replenishing surge, juxtaposed against the lower totals seen in spring and late summer. Notably, month's precipitation peaks exceed January's 54 mm (2.1 in) and February's 56 mm (2.2 in), hinting at winter's ability to usher in moisture-rich conditions. Thus, December not only serves as a transition into the wetter winter months but also reinforces the trend of fluctuating rainfall patterns characteristic of Oceanside's climate.

December Precipitation Trends in Oceanside

The chart displays monthly precipitation patterns in Oceanside, with values for each month alongside December's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec54564523143313102163
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

December Humidity in Oceanside

In Oceanside, California, December brings a notable shift in humidity, settling at 71%—a slight drop from the more humid months of January and February, which boast 74% and 79%, respectively. As the year progresses, humidity levels tend to decrease, peaking mid-winter before gradually declining through the summer months. The trend shows a predominant low during late summer and early fall, with August and September recording their lowest at 69% and 68%. As December rolls in, residents can expect a refreshing atmosphere, hanging onto that crisp and comfortable coastal charm that defines the season. Overall, the variations create a tapestry of moisture that captures the essence of Oceanside’s climate throughout the year.

December Average Humidity in Oceanside

This chart illustrates the average monthly humidity levels in Oceanside, with December's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how December's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec74%79%75%71%70%72%73%69%68%67%68%71%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Oceanside

In December, Oceanside experiences a UV Index of 4, placing it in the moderate exposure category. This means that while the sun's rays are less intense compared to the summer months, individuals should still take care to avoid excessive sun exposure, with a recommended burn time of about 30 minutes. As the year progresses, we observe a clear pattern of increasing UV levels, peaking at an extreme rating of 11 in May and June. Following this peak, the indices gradually decline, reaching their lowest point again in December. For a deeper dive into monthly UV trends and tips on sun safety, check out Oceanside UV Index.

Maximum UV Index Levels in Oceanside for December

The chart shows the monthly maximum UV Index (UVI) for Oceanside in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec468101112111010754
Data source: Oceanside December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

December Sunshine in Oceanside

As December rolls into Oceanside, the coastal city experiences a charming decline in sunshine hours, totaling 225 hours for the month. This drop marks a noticeable contrast to the sun-soaked peak of summer, where July basked in an impressive 376 hours of radiant light. The trend of diminishing daylight unfolds gradually, with each month from May’s 347 hours to November’s 254 hours leading into December’s shorter days. However, the allure of Oceanside's more tempered winter sun still offers a delightful reprieve, making it an inviting destination for those seeking a serene escape amidst the holiday hustle.

Monthly Sunshine Duration in Oceanside: December Highlighted

The December sunshine duration represents the total number of hours Oceanside experiences direct sunlight during the month of December, excluding cloudy or obstructed periods. This chart compares the sunshine duration of December with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec189h238h291h317h347h363h376h359h314h292h254h225h
Data source: Oceanside December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Oceanside During December

In Oceanside, December brings a 46% chance of sunny weather, marking a dip compared to the preceding months. This trend reveals that as the year winds down, the likelihood of sunshine decreases from the higher probabilities observed in October and November, both at 63%. While December's sunshine rates are noticeably lower, it remains consistent with the shifting seasonal patterns, as the sun's presence tends to wane as winter approaches. Despite the reduced chance of clear skies, there are still opportunities to enjoy occasional sunny days amidst the cooler temperatures.

Percentage of Sunny Days in December in Oceanside

The chart illustrates the percentage of sunny days in Oceanside throughout the year, with December highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Oceanside experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec59%59%62%47%34%45%53%56%58%63%63%46%
Data source: Oceanside December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Oceanside in December

As December settles in Oceanside, the daylight duration reaches its annual low of just 9 hours per day, marking the end of a gradual decline that begins after the long summer days of June and July. From the bright glow of 14 hours in the height of summer, the sun steadily retreats, offering a shorter but more intimate connection with nature. As the year transitions into winter, this decrease in daylight not only influences the local climate but also invites the community to embrace the cozy charm of the season, celebrating the beauty of the longer evenings and festive atmospheres that December brings.

Average Daylight Hours in Oceanside for December

The chart illustrates the variation in daylight duration in Oceanside throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 13m11h12h13h 1m13h 52m14h 18m14h 4m13h 18m12h 19m11h 18m10h 25m9h 58m
Data source: Oceanside daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Oceanside

As December arrives in Oceanside, the coastal winds begin to pick up, boasting an average speed of 2.9 m/s (6 mph). This notable increase marks a shift from the gentler breezes of early winter, where wind speeds hovered around 2.0 to 2.4 m/s in the preceding months. The steady and slightly stronger winds in December echo those of March and April, suggesting a seasonal rhythm that invites both surfers and beachcombers to embrace the ocean's refreshing touch. As the year winds down, the invigorating gusts serve as a reminder of nature's dynamic beauty along the California coast.

Average December Wind Speed in Oceanside

The chart displays monthly wind speed patterns in Oceanside, with values for each month shown alongside December's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how December's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.72.22.92.82.72.52.32.32.32.42.02.9 m/s
Data source: Oceanside December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Oceanside Compares to Other Months

The weather in Oceanside 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 Oceanside and find detailed weather information for every month.

In December, the weather features a comfortable range, with average temperatures hovering around 15°C (59°F) and highs reaching up to 26°C (78°F). The month experiences moderate rainfall, totaling 63 mm (2.5 in) over five days, along with a humidity level of 71%. In contrast, January sees a slight increase in minimum temperatures, averaging around 8°C (47°F) and a max of 27°C (82°F), while the average temperature dips to 14°C (58°F). Precipitation is slightly lower at 54 mm (2.1 in) over the same five days, with humidity rising to 74%. For a more detailed overview of January weather, you can check Oceanside weather in January.

In comparing the weather of December and February, we notice that both months experience relatively mild temperatures, with December averaging 15°C (59°F) and February slightly cooler at 14°C (58°F). The minimum temperatures for both months are similar, starting at 7°C (46°F) in December and 7°C (44°F) in February. However, December tends to have higher maximum temperatures, peaking at 26°C (78°F), compared to February, which reaches a maximum of 25°C (78°F). Precipitation levels are fairly close, with December receiving 63 mm (2.5 in) over 5 days and February totaling 56 mm (2.2 in) across 6 days, while humidity is slightly higher in February at 79% compared to December’s 71%. For more detailed insights into February weather, you can visit Oceanside weather in February.

In December, temperatures range from a minimum of 7°C (46°F) to a maximum of 26°C (78°F), with an average of 15°C (59°F). The month brings about 63 mm (2.5 in) of precipitation over 5 days, contributing to a humidity level of 71%. In contrast, March records slightly warmer minimum temperatures at 9°C (48°F) and a lower maximum of 24°C (75°F), with the same average of 15°C (59°F). Precipitation in March totals 45 mm (1.8 in) over 9 days, resulting in a higher humidity of 75%. For more details on the weather in March, you can visit Oceanside weather in March.

In December, the weather tends to be mild with temperatures ranging from a minimum of 7°C (46°F) to a maximum of 26°C (78°F), averaging around 15°C (59°F). The month sees about 63 mm (2.5 in) of precipitation over approximately 5 days, creating a slightly humid atmosphere with an average humidity of 71%.

In contrast, April experiences slightly warmer conditions, with minimum temperatures starting at 10°C (50°F) and maximums reaching up to 29°C (85°F), yielding an average of 16°C (61°F). The precipitation drops significantly to 23 mm (0.9 in) across just 3 days, maintaining a comparable humidity level of 70%.

For a more detailed look at the weather during this time, you can check Oceanside weather in April.

In December, temperatures range from a minimum of 7°C (46°F) to a maximum of 26°C (78°F), with an average of 15°C (59°F). This month sees about 63 mm (2.5 in) of precipitation spread over five days and maintains a humidity level of 71%. In contrast, May presents slightly warmer conditions, with temperatures varying from a minimum of 12°C (53°F) to a maximum of 26°C (79°F) and an average of 17°C (63°F). Precipitation is significantly lower at 14 mm (0.6 in) across just four days, while humidity remains relatively stable at 70%. For a more detailed look at the weather specifics for May, check out Oceanside weather in May.

When comparing the weather in December and June, distinct differences emerge. December offers cooler temperatures, with a minimum of 7°C (46°F) and an average of 15°C (59°F), accompanied by more substantial precipitation of 63 mm (2.5 in) spread over about 5 days. In contrast, June features milder conditions, with a minimum of 14°C (57°F) and an average of 19°C (66°F), as well as significantly less rain, totaling just 3 mm (0.1 in) with no rainy days. Interestingly, humidity levels remain quite similar in both months, hovering around 71-72%. For a detailed look at the nice weather conditions typical of June, you can check Oceanside weather in June.

December weather tends to be milder with temperatures ranging from a minimum of 7°C (46°F) to a maximum of 26°C (78°F) and an average of 15°C (59°F). This month also sees higher precipitation, with about 63 mm (2.5 in) falling over approximately five days, contributing to a humidity level of 71%. In contrast, July experiences significantly warmer temperatures, with minimums around 17°C (62°F) and maximums peaking at 35°C (94°F), averaging 21°C (71°F). Importantly, July boasts much drier conditions, with only 3 mm (0.1 in) of rain and no precipitation days, all while maintaining a similar humidity level of 73%. For more details on how July shapes up, you can check Oceanside weather in July.

December and August exhibit distinct weather patterns, with December bringing cooler temperatures, ranging from a low of 7°C (46°F) to a high of 26°C (78°F) and an average of 15°C (59°F). This month experiences moderate precipitation, totaling 63 mm (2.5 in) over about 5 days, coupled with a humidity level of 71%. In contrast, August is markedly warmer, with temperatures ranging from a minimum of 17°C (64°F) to a maximum of 30°C (86°F) and an average of 22°C (72°F). Remarkably, August sees minimal rainfall, with only 1 mm (0.0 in) and no rainy days, accompanied by slightly lower humidity at 69%. For more detailed insights into August conditions, check out Oceanside weather in August.

In December, temperatures range from a cooler minimum of 7°C (46°F) to a pleasant maximum of 26°C (78°F), with an average of 15°C (59°F). The month experiences about 63 mm (2.5 in) of precipitation over five days, contributing to a higher humidity level of 71%. In contrast, September offers much warmer weather, with minimums around 15°C (60°F) and maximums soaring up to 34°C (93°F), averaging 22°C (72°F). Rainfall is minimal in September, with only 3 mm (0.1 in) over just one day, and humidity is relatively lower at 68%. For more details on September weather specifics, you can check Oceanside weather in September.

In comparing December and October weather, December tends to be cooler and wetter, with average temperatures ranging from a minimum of 7°C (46°F) to a maximum of 26°C (78°F) and approximately 63 mm (2.5 inches) of precipitation over 5 days. In contrast, October enjoys warmer temperatures ranging from a minimum of 11°C (52°F) to a scorching maximum of 36°C (97°F), accompanied by much less rain, amounting to only 10 mm (0.4 inches) over just 1 day. Humidity levels are slightly higher in December at 71%, compared to 67% in October. For a more detailed look at October weather specifically, you can visit Oceanside weather in October.

When comparing the weather in December to that of November, December experiences slightly cooler temperatures, with an average minimum of 7°C (46°F) and a maximum of 26°C (78°F), compared to November's minimum of 10°C (49°F) and maximum of 29°C (84°F). Additionally, December has a higher level of precipitation, measuring 63 mm (2.5 in) over 5 days, whereas November sees only 21 mm (0.8 in) over 2 days. Despite the increased rainfall in December, the humidity levels remain relatively similar, with December at 71% and November at 68%. For more detailed insights into November's weather, you can view the information here: Oceanside weather in November.

Compare Oceanside's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Oceanside

As December settles into Oceanside, the weather takes on a cooler, more refreshing character compared to the warmer months. While daytime temperatures can still reach a pleasant 26°C (78°F), the evenings bring a crisp chill, dropping to 7°C (46°F). This transition contributes to an average temperature of 15°C (59°F), creating an inviting atmosphere perfect for winter strolls along the beach. December also sees an increase in humidity levels, hovering around 71%, and registers a modest amount of precipitation with about 63 mm (2.5 in) over just 5 days. As the festive season unfolds, the weather invites both locals and visitors to embrace the unique charm of Oceanside. For a deeper understanding of how this month compares to others, explore the full details at Oceanside Climate.