San Antonio, TX Climate

Summary Graph

The summary climate graph for San Antonio, TX shows a selection of temperature, rainfall and snow minimum, mean and maximum measures over the course of a year. Click on each of the measures in the key to toggle them on and off.

Graph of average and extreme temperature ranges by day for San Antonio, TX.


The warmest month in Randolph Air Force Base, San Antonio, Texas is August with an average high temperature of 95.3°F. The hottest day on record was August 28 2011 when the temperature hit 110.7°F. During January the overnight temperature drops to an average of 42.1°F with the lowest temperature of 8.2°F being recorded on December 23 1989.

Warmest Days

Warmest Months

Coldest Days

Coldest Months

The warmest days on record are:

28 Aug 2011110.7°F
15 Jun 1998109.4°F
26 Jul 1954107.2°F
9 Aug 1962106.3°F
9 Jul 1939105.3°F

The warmest months on average were:

August 2011102.3°F
July 1998101.4°F
July 2009100.6°F
August 2009100.3°F
July 1980100°F

The coldest days on record are:

23 Dec 19898.2°F
31 Jan 19498.4°F
12 Jan 19628.4°F
2 Feb 195112.4°F
14 Jan 196412.4°F

The coldest months on average were:

January 196233.6°F
January 194033.6°F
January 196334°F
January 198534.5°F
December 198936.2°F


The wettest month by average rainfall in San Antonio, TX is May with an average of 2.0 inches of rain falling on 11 to 12 days.Although in March it typically rains on more days with 1.1 inches falling in 11 to 12 days. The driest month by average rainfall in San Antonio, TX is February with an average of 0.9 inches of rain falling on 10 to 11 days. Although in July it typically rains on less days with 1.3 inches falling in 6 to 7 days

Wettest Days

The wettest days on record are:

18 October 199816.3 inches
8 October 19945.6 inches
4 October 20094.9 inches
12 October 19863.7 inches
26 October 19753.4 inches

Wettest Months

The wettest months on record are:

October 199822.1 inches
September 197315.5 inches
July 200714.1 inches
September 201012.6 inches
October 200912.3 inches

Driest Months

The driest months on record are:

May 19380 inches
June 19380 inches
July 19380 inches
August 19380 inches
September 19380 inches