San Antonio Temperatures: Averages by Month

The numbers here tell you how hot and cold the weather usually is in San Antonio, Texas during each month of the year.

The average high and low temperatures are listed below by month and annually for San Antonio, in both degrees Fahrenheit and Celsius.

Maximums and minimums are only part of the temperature picture. To fill in the rest, there's information on how many days a month get above or below a given temperature.

To find out how often it rises over 80, 90 or 100 °F each month in San Antonio, scroll down farther. There are also counts of nights with warm temperatures and days with cold weather.

The first set of high and low temperatures are averages for 2010 to 2019. Everything else here is based on 1991 to 2020 weather.

10-year temperature averages for San Antonio, 2010 to 2019
High °F Low °F   High °C Low °C
64 41 January 18 5
68 46 February 20 8
75 53 March 24 12
81 60 April 27 15
87 67 May 31 20
93 74 June 34 23
96 76 July 36 24
98 77 August 37 25
92 72 September 33 22
83 61 October 28 16
72 51 November 22 11
65 44 December 19 7
81 60 Year 27 16
30-year temperature averages for San Antonio, 1991 to 2020
High °F Low °F   High °C Low °C
63 41 January 17 5
68 45 February 20 7
74 52 March 23 11
80 58 April 27 15
87 66 May 30 19
92 73 June 34 23
95 75 July 35 24
96 75 August 36 24
90 70 September 32 21
82 60 October 28 16
72 50 November 22 10
65 42 December 18 6
80 59 Year 27 15

Days of Hot Weather in San Antonio

Normally every day from April to October in San Antonio is above 60 degrees Fahrenheit, as are most days in winter months. Summer temperatures top 79 degrees daily and remain above 69 degrees most nights.

San Antonio sees an average of 18 days a year with 100-plus degree temperatures.

Days per month in San Antonio of at least 80, 90 or 100 °F
  80 °F
27 °C
90 °F
32 °C
100 °F
38 °C
January 1 0 0
February 4 0 0
March 10 1 0
April 19 3 0
May 28 12 0
June 30 24 2
July 31 29 6
August 31 29 9
September 28 20 1
October 23 6 0
November 7 0 0
December 2 0 0
Year 213 122 18
Average number of days monthly in San Antonio that stay above 50, 60 or 70 °F
  50 °F
10 °C
60 °F
16 °C
70 °F
21 °C
January 5 1 0
February 9 3 0
March 18 8 0
April 24 14 2
May 31 26 11
June 30 30 23
July 31 31 30
August 31 31 29
September 30 27 17
October 26 17 5
November 14 6 1
December 7 2 0
Year 255 195 118

How Often San Antonio Has Cold Temperatures

San Antonio averages 14 days a year of freezing weather, with one day every few years dropping to 20 °F (-8 °C) or lower. Freezing temperatures normally occur from November to March.

Most freezing nights are followed by a daytime thaw. Twice a decade, on average, the thermometer never rises above freezing for the enitre day.

References

Jay Lawrimore, Ron Ray, Scott Applequist, Bryant Korzeniewski, Matthew Menne. 2016. Global Summary of the Month and Year, Version 1.0. NOAA National Centers for Environmental Information.

NOAA National Centers for Environmental Information (NCEI). Climate Normals.

San Antonio Weather
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