Climate Insights for San Antonio

The climate in San Antonio is cold. The average annual temperature is -13°C and approximately 258mm of precipitation falls per year. December is the wettest month, receiving around 33mm 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: December, November, October. The coldest months are April, March, June, when temperatures can drop to -23°C. San Antonio experiences heavy snowfall, typically from January through December.

Temperatures in San Antonio vary considerably across the year, with a 22°C difference between the coldest and warmest months. December is the warmest month, though highs remain moderate at -1°C with a mean of -1°C. April brings the harshest conditions, with lows dropping to -23°C and an average temperature of -21°C. Daily temperature variation is modest, with an average difference of 3°C between highs and lows. The sharpest temperature change occurs between February and March, with a 8°C shift in average temperatures.

San Antonio is a quite dry location, receiving approximately 258mm of precipitation annually, which averages out to around 21mm per month. The wettest month is January, averaging 33mm of rainfall. February and May also tend to see above-average precipitation. The driest month is March, with just 1mm. That's 32mm less than January, 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 receives heavy snowfall, accumulating around 258cm annually from January through December. The snowiest month is January, with approximately 33cm. Winter travel should account for significant snow cover.

San Antonio is relatively calm, with an average annual wind speed of 8km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is October, averaging 13km/h, though still comfortable for most outdoor activities. The calmest conditions occur in June, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. Wind speeds vary significantly across the year, with a 11km/h difference between the calmest and windiest months. This level of variation is worth factoring into travel plans. Wind tends to pick up during the summer months. The seasonal averages are 5km/h in winter, 13km/h in spring, 9km/h in summer, 7km/h in autumn.

It is currently winter in San Antonio, which began on June 21, 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 December at around -1°C, while the coldest stretch bottoms out in April near -23°C. Spring is next, beginning on September 23, 2026 — 21 days from now.

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. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. 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.