Last updated: August 22, 2025
In December, the average temperature in San Antonio, Argentina hovers around 20°C (68°F). Expect a minimum of 8°C (47°F) and a maximum of 31°C (88°F) during this month. Precipitation is quite notable, with an average of 272 mm (10.7 in) spread over 23 days, and the air carries an average humidity of 77%. Prepare for a mix of warm days and occasional rain!
In December in San Antonio, the average temperature is 20°C (68°F). The maximum can reach 31°C (88°F) and the minimum can be as low as 8°C (47°F). This makes it a great time to enjoy outdoor activities while being prepared for varying weather conditions.
In San Antonio in December, the precipitation amount is 272 mm (10.7 in) spread over 23 days.
In San Antonio in December, humidity is 77%. With an average temperature of 20°C (68°F), this humidity feels like a warm, sticky embrace, making it essential for travelers to stay hydrated and take breaks in shaded areas to avoid feeling sluggish in the heat.
In San Antonio in December, the maximum UV index is 16, which corresponds to an extreme Exposure Category. The time to burn is just 10 minutes, making it crucial to take protective measures. For detailed information, you can refer to 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 | 21°C (69°F) | 223 mm (8.8 inches) | 84% | extreme |
| February Weather | 19°C (67°F) | 237 mm (9.3 inches) | 87% | extreme |
| March Weather | 18°C (65°F) | 282 mm (11.1 inches) | 88% | extreme |
| April Weather | 16°C (61°F) | 267 mm (10.5 inches) | 85% | extreme |
| May Weather | 13°C (56°F) | 155 mm (6.1 inches) | 74% | very high |
| June Weather | 11°C (52°F) | 55 mm (2.2 inches) | 56% | high |
| July Weather | 11°C (52°F) | 45 mm (1.8 inches) | 47% | high |
| August Weather | 12°C (55°F) | 52 mm (2.1 inches) | 44% | very high |
| September Weather | 15°C (60°F) | 85 mm (3.4 inches) | 57% | extreme |
| October Weather | 18°C (64°F) | 201 mm (7.9 inches) | 55% | extreme |
| November Weather | 19°C (66°F) | 241 mm (9.5 inches) | 70% | extreme |
| December Weather | 20°C (68°F) | 272 mm (10.7 inches) | 77% | extreme |