Climate Insights for San Antonio

The climate in San Antonio is temperate. The average annual temperature is 14°C and approximately 327mm of precipitation falls per year. June is the wettest month, receiving around 97mm of rainfall. San Antonio is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: January, February, December. The coldest months are July, June, August, when temperatures can drop to 5°C.

San Antonio sees moderate temperature variation throughout the year, ranging from 5°C to 25°C. January is the warmest month, though highs remain moderate at 25°C with a mean of 19°C. July is the coolest month, with minimum temperatures around 5°C and an average of 9°C. On average, daily temperatures fluctuate by about 11°C between overnight lows and afternoon highs. The sharpest temperature change occurs between March and April, with a 3°C shift in average temperatures.

San Antonio is a quite dry location, receiving approximately 327mm of precipitation annually, which averages out to around 27mm per month. The wettest month is June, averaging 97mm of rainfall. July and August also tend to see above-average precipitation. The driest month is February, with just 0mm. That's 97mm less than June, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.

San Antonio is mildly breezy, with an average annual wind speed of 16km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is November, averaging 19km/h, though still comfortable for most outdoor activities. The calmest conditions occur in May, with average winds dropping to 12km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 7km/h gap between the calmest and windiest months. Wind tends to pick up during the summer months. The seasonal averages are 13km/h in winter, 17km/h in spring, 18km/h in summer, 14km/h in autumn.

It is currently autumn in San Antonio, which began on March 20, 2026. San Antonio is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in January at around 25°C, while the coldest stretch bottoms out in July near 5°C. Winter is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit San Antonio is during January, February, March, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 18°C with modest rainfall averaging 3mm per month. By contrast, July can be quite cold with temperatures dropping to 5°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.

The table below shows monthly climate averages for San Antonio based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.