Last updated: August 22, 2025
In December, the average temperature in San Antonio, Argentina is a pleasant 19°C (66°F). Expect minimums dipping to 8°C (46°F) and maximums soaring up to 31°C (88°F). However, be prepared for some rain, with an average precipitation of 230 mm (9.0 in) spread over 21 days. Humidity levels hover around 61%, adding to the overall climate experience.
In December in San Antonio, the average temperature is 19°C (66°F), with maximums reaching 31°C (88°F) and minimums dropping as low as 8°C (46°F). This diverse temperature range makes it an ideal time for travelers to enjoy both warm days and cooler evenings while exploring the area.
In San Antonio in December, the precipitation amount is 230 mm (9.0 in) spread over 21 days, indicating a relatively wet period.
In San Antonio in December, humidity is 61%. With an average temperature of 19°C (66°F), this humidity feels like a warm, gentle embrace, making it ideal for leisurely exploration, though you might want to keep a light jacket handy for cooler evenings.
In San Antonio in December, the maximum UV index reaches an alarming 15, which falls into the extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to take precautions. For detailed information, you can check the Hourly UV Index in San Antonio.
UV Risk Categories
Weather in San Antonio varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in San Antonio, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 20°C (68°F) | 235 mm (9.3 inches) | 63% | extreme |
| February Weather | 19°C (66°F) | 210 mm (8.3 inches) | 66% | extreme |
| March Weather | 17°C (63°F) | 207 mm (8.1 inches) | 68% | extreme |
| April Weather | 15°C (60°F) | 181 mm (7.1 inches) | 83% | very high |
| May Weather | 11°C (53°F) | 97 mm (3.8 inches) | 82% | high |
| June Weather | 8°C (47°F) | 43 mm (1.7 inches) | 72% | moderate |
| July Weather | 8°C (46°F) | 26 mm (1.0 inches) | 57% | high |
| August Weather | 10°C (50°F) | 14 mm (0.5 inches) | 42% | high |
| September Weather | 13°C (56°F) | 51 mm (2.0 inches) | 51% | very high |
| October Weather | 16°C (61°F) | 103 mm (4.1 inches) | 47% | extreme |
| November Weather | 18°C (64°F) | 170 mm (6.7 inches) | 58% | extreme |
| December Weather | 19°C (66°F) | 230 mm (9.0 inches) | 61% | extreme |