Last updated: February 24, 2025
In December, San Antonio experiences a varied climate, with maximum temperatures reaching 29°C (85°F) and dipping to a chilly minimum of -3°C (27°F). The month holds an average temperature of 13°C (56°F), providing a mild winter ambiance. Precipitation is notable with 57 mm (2.3 in) spread over approximately 7 days, contributing to the city's high humidity levels of 86%. This combination of warmth, occasional rain, and elevated humidity creates a unique and refreshing atmosphere typical of a Texas winter.
In December, San Antonio experiences a notable shift as temperatures begin to cool, marking the transition into winter. The month opens with minimums dipping to -3°C (27°F) and daily averages settling around 13°C (56°F), providing a crisp yet manageable chill in the air. As the month progresses, daytime highs can still reach a comfortable 29°C (85°F), showcasing the city's mild climate even in the depths of winter. This blend of cooler nights and warmer afternoons creates an inviting atmosphere for outdoor activities, inviting residents and visitors alike to enjoy the festive season under the Texas sun.
December in San Antonio brings moderate precipitation, with an average of 57 mm (2.3 in) over approximately seven days of rainfall. This marks a slight decrease from the wetter months of May and September, which see significantly higher totals, yet still shows a typical end-of-year trend where rain becomes less frequent as the region transitions into winter. Interestingly, December’s precipitation levels are comparable to those of February, suggesting a consistent pattern of diminished rainfall as the year concludes. With the holiday season in full swing, the occasional drizzle may provide a refreshing contrast to the often balmy Texas weather, enhancing the overall festive atmosphere.
December brings a notable rise in humidity in San Antonio, reaching an average of 86%, the highest level of the year. This increase follows a pattern observed in the months leading up to winter, where humidity peaks in late fall with 81% in November. As temperatures drop in December, moisture in the air tends to accumulate, contrasting sharply with the much drier months of late summer, such as 58% in August and 66% in July. Overall, the trend highlights a shift toward a more humid atmosphere as the year closes, providing a unique feel to the city's winter climate.
As December rolls into San Antonio, the UV Index dips to a moderate level of 5, marking a refreshing contrast to the extreme values seen during the summer months when indexes peaked at 12. With a burn time of approximately 30 minutes, residents can enjoy outdoor activities with less risk of sunburn compared to the scorching days of July and August. Notably, this seasonal trend reveals a significant decline in UV exposure as the year ends, after months of intense sunshine typically characterized by very high to extreme levels. As you prepare for winter outings, remember to check the San Antonio UV Index for updated information and keep your skin protected!
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In San Antonio, December marks a transition into winter, yet it still boasts an impressive 218 hours of sunshine. This month continues the trend established throughout the year, where sunshine hours peak during the warmer months, with June and July shining brightest at over 340 hours each. As the year closes, December gracefully ushers in shorter days but retains a generous amount of sunlight, laying the groundwork for the radiant spring that follows. Despite the dip from November's 223 hours, December's sunshine cultivates a vibrant backdrop for the festive season, reminding residents and visitors alike that warmth can be found even as temperatures cool.
In San Antonio, the likelihood of sunny weather displays a distinct seasonal trend throughout the year. Notably, December offers a 37% chance of sunshine, which is among the lowest percentages and underscores the transition into winter. This percentage reflects a dip from the 61% chance seen in September, where the summer sunshine still lingers. Following September, October and November maintain relatively moderate probabilities of sunny days at 52% and 53%, respectively. This implies that, while December brings a cooler climate and less sun, the preceding months provide ample opportunity for sunshine before the year's end. The overall trajectory reveals a gradual decline in sunny days as the year approaches winter, suggesting December is a month where overcast skies may take precedence over bright, sunny ones.
As December unfolds in San Antonio, daylight reaches its nadir with just 10 hours of sunlight each day, mirroring the trend seen in both November and January. This month marks the end of the gradual decline in daylight that begins after the summer solstice, where the city enjoys a generous 13 hours from June through August. Interestingly, daylight starts to shorten after May, decreasing steadily until December. Following this pattern, residents can expect longer days as the year advances into spring, with 12 hours of daylight becoming standard by March and April. This cyclical progression offers a rhythmic dance of light and dark, inviting San Antonians to savor the crisp, cool days of winter while looking forward to the upcoming brightness of spring.
In December, San Antonio experiences a gentle breeze with an average wind speed of 2.9 m/s (7 mph), slightly lower than the preceding months. This trend of tapering winds is consistent as the year progresses, peaking in early spring, particularly in March at 4.0 m/s (9 mph), before descending into the calmer summer months where it dips to 2.6 m/s (6 mph) in July and August. As the year winds down, the transition to winter heralds a slight increase back to 3.0 m/s (7 mph) in November. However, December settles in with a serene calm, embodying the tranquil spirit of the season while still inviting residents to enjoy the mild, cool air that characterizes the festive month.
The weather in San Antonio 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 Antonio and find detailed weather information for every month.
In December, temperatures in San Antonio range from a chilly minimum of -3°C (27°F) to a warm maximum of 29°C (85°F), with an average temperature of 13°C (56°F). The month also experiences considerable humidity at 86% and sees about 57 mm (2.3 in) of precipitation over 7 days. In contrast, January presents slightly colder conditions, with minimum temperatures dropping to -7°C (20°F) and an average of 11°C (53°F), peaking at 27°C (81°F). Precipitation decreases to 44 mm (1.7 in) and occurs over 6 days, along with a lower humidity of 79%. For more insights, check San Antonio weather in January.
When comparing the weather in December and February, we observe some notable differences and similarities. December experiences a wider temperature range, with a minimum of -3°C and a maximum of 29°C, while February sees more extreme low temperatures down to -12°C but a slightly higher maximum of 31°C. Both months have similar average temperatures around 13°C (56°F), yet February tends to be colder at night. Precipitation levels are similar, with December receiving 57 mm over seven days, while February sees about 58 mm over ten days. Interestingly, February has lower humidity at 79%, compared to December's high of 86%. For an in-depth look at February's weather specifically, visit San Antonio weather in February.
In December, temperatures tend to be cooler with a minimum of -3°C (27°F) and an average high of 13°C (56°F), while March sees a noticeable warm-up, featuring a similar minimum of -3°C but an average temperature of 18°C (65°F). The maximum temperatures in March can reach up to 33°C (91°F), significantly higher than December's peak of 29°C (85°F). Despite the slightly higher precipitation in March at 62 mm (2.5 in) compared to December's 57 mm (2.3 in), the humidity is lower in March, averaging 74% opposed to December's 86%. For more detailed information, you can check San Antonio weather in March.
December and April present quite different weather patterns. In December, temperatures range from a chilly minimum of -3°C (27°F) to a mild maximum of 29°C (85°F), with an average of 13°C (56°F). The month experiences about 57 mm (2.3 in) of precipitation over approximately 7 days, accompanied by high humidity at 86%. In contrast, April sees warmer temperatures, with a minimum of 3°C (37°F) and a maximum reaching 35°C (95°F), averaging 21°C (70°F). Precipitation slightly increases to 71 mm (2.8 in) over 8 days, while humidity decreases to 76%. For more details, check San Antonio weather in April.
December and May present markedly different weather experiences. In December, temperatures range from a chilly minimum of -3°C (27°F) to a comfortable maximum of 29°C (85°F), with an average of 13°C (56°F). The month sees about 57 mm (2.3 in) of precipitation over 7 days and boasts high humidity at 86%. In contrast, May offers significantly warmer temperatures, with minimums around 11°C (51°F) and highs reaching up to 37°C (99°F), resulting in an average of 25°C (77°F). Precipitation increases to 130 mm (5.1 in) over 15 days, while humidity slightly decreases to 81%. For more details about the May weather conditions, check out San Antonio weather in May.
In December, the weather is marked by cooler temperatures, with lows reaching -3°C (27°F) and an average of 13°C (56°F), making it a much chillier month compared to June. December experiences about 57 mm (2.3 in) of precipitation over 7 days, accompanied by high humidity levels of 86%. In contrast, June is significantly warmer, with minimum temperatures around 18°C (64°F) and averages peaking at 28°C (83°F), and maximums soaring up to 39°C (103°F). This month also sees increased precipitation at 78 mm (3.1 in) over 12 days, though the humidity is somewhat lower at 76%. For more details about June's climate, refer to San Antonio weather in June.
December and July present stark contrasts in weather, reflecting the seasonal differences that characterize these months. In December, temperatures can dip as low as -3°C (27°F), with an average of 13°C (56°F) and reaching up to 29°C (85°F). The humidity is quite high at 86%, and precipitation occurs on about 7 days, totaling 57 mm (2.3 in). Conversely, July boasts much warmer temperatures, with a minimum of 17°C (64°F), an average of 29°C (85°F), and extremes reaching up to an impressive 41°C (106°F). The humidity is significantly lower at 66%, and rainfall slightly increases with 69 mm (2.7 in) spread over 8 days. For more details on July weather, you can check San Antonio weather in July.
December and August present starkly contrasting weather conditions. In December, temperatures range from a chilly minimum of -3°C (27°F) to a pleasant average of 13°C (56°F), peaking at a warm 29°C (85°F). Humidity levels soar to 86%, accompanied by about 57 mm (2.3 in) of precipitation over 7 days. In contrast, August boasts a much warmer climate, with temperatures starting at a minimum of 20°C (69°F), averaging 30°C (86°F), and reaching highs of 40°C (103°F). The month sees similar precipitation levels of 56 mm (2.2 in) but with lower humidity at 58% over just 6 days. For further details, you can explore the San Antonio weather in August.
In comparing the weather of December and September, we notice significant differences in temperature and humidity. December experiences cooler temperatures, with a minimum of -3°C (27°F) and an average of 13°C (56°F), while September enjoys much warmer weather, starting with a minimum of 12°C (54°F) and an average high of 27°C (80°F). Additionally, September is marked by higher maximum temperatures that can reach up to 39°C (102°F). Precipitation levels also differ, with December having 57 mm (2.3 in) over approximately 7 days, in contrast to September, which sees a greater amount of rain totaling 117 mm (4.6 in) across about 10 days. Moreover, December has a higher humidity level at 86%, compared to September's 65%. For more specifics on September's weather patterns, you can visit San Antonio weather in September.
In comparing the weather conditions of December and October, we observe notable differences in temperature and humidity. December experiences cooler temperatures, with a minimum of -3°C (27°F) and an average of 13°C (56°F), while October offers a much warmer range, with a minimum of 3°C (37°F) and an average of 22°C (72°F). The maximum temperatures in October can soar as high as 37°C (98°F), compared to December's peak of 29°C (85°F). Moreover, October sees more precipitation, accumulating 89 mm (3.5 in) over about 10 days, whereas December has 57 mm (2.3 in) over 7 days. Humidity levels are also higher in December at 86%, compared to October's 74%. For a deeper look into October's climate specifics, you can check out San Antonio weather in October.
In comparing the weather conditions of December and November, December tends to be slightly cooler, with an average temperature of 13°C (56°F) and a minimum of -3°C (27°F), while November has a higher average temperature of 16°C (61°F) and a minimum temperature of -4°C (25°F). Additionally, December experiences a maximum temperature of 29°C (85°F), compared to November's peak of 32°C (90°F). Precipitation also increases slightly in December, with 57 mm (2.3 in) over 7 days, compared to 46 mm (1.8 in) over 6 days in November. The humidity levels are higher in December at 86%, while November has a lower humidity of 81%. For a more detailed look at November's weather, you can visit San Antonio weather in November.
As December rolls into San Antonio, the weather transforms into a cooler, more refreshing experience compared to the typically warmer months. With an average temperature comfortably settling around 13°C (56°F), residents enjoy a pleasant reprieve from the heat, although occasional cold snaps can dip down to chilling -3°C (27°F). While the month sees about 57 mm (2.3 inches) of precipitation over roughly seven days, humidity levels remain quite high at 86%, adding a crispness to the air. Whether you're taking in the holiday lights or enjoying outdoor activities, December's unique climate invites a different rhythm to life in the city. For more insights into what to expect during the year round, check out San Antonio Climate.