The climate of San Antonio is subtropical, with mild winters and very hot, muggy summers.
The city is located in southern Texas, about 200 km (125 mi) away from the sea.
Winter is mild, but there may be variations in temperature. Even in the middle of winter, there can be hot days, with highs of 25 °C (77 °F) and more. In other circumstances, it can get cold at night, and the temperature can drop below freezing. Very rarely, as happened in December 2017, it can also snow.
In summer, on the hottest days, the temperature can reach and exceed 40 °C (104 °F). In 2011, the temperature dropped to -7 °C (19 °F) in February, while it reached 43 °C (109 °F) in July. In September 2000, it reached 44 °C (111 °F).
From time to time, the city can be reached by the remnants of a hurricane, coming from the Gulf of Mexico or the Pacific. In general, hurricanes weaken when they penetrate inland, however, they can still bring abundant rains. The hurricane season runs from June to November, although they are more likely from August to October, with a peak in September.
The average temperature of the coldest month (January) is of 11 °C (52 °F), that of the warmest month (August) is of 29.7 °C (85 °F). Here are the average temperatures.

Precipitation amounts to 820 millimeters (32.3 inches) per year: so, it is at an intermediate level. The rainiest seasons are spring and autumn, due to the clash of air masses. San Antonio is just outside the "tornado alley", however tornadoes can occasionally occur in the period April-June (and more rarely in autumn). Here is the average precipitation.

On average, there are around 2,630 sunshine hours per year. Here are the average sunshine hours per day.

Best Time

To visit San Antonio, you can choose spring and autumn (in particular, from mid-March to mid-April and from mid-October to mid-November), to avoid the summer heat. In winter, there are long mild periods, but some very cold days cannot be excluded.