August weather in San Marcos, TX
The average temperature in San Marcos in August is 85.2°F (73.7°F–96.8°F). Average precipitation: 2.60 inches.
August is a summer month in San Marcos, and is warmer than the annual average of 68.6°F. Daily temperatures swing about 23.1°F between overnight low and afternoon high. Expect about 5 days with precipitation. Daylight averages about 13h 5m. For travel, August is hot.
Avg High
96.8°F
Avg Low
73.7°F
Precipitation
2.60 in
Daylight
13h 5m
August records in San Marcos
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 105.1°F (1922) | 61.0°F (1936) | 1.91 in (1978) |
| August 2 | 106.0°F (1923) | 61.0°F (1936) | 2.80 in (1948) |
| August 3 | 107.1°F (1922) | 60.1°F (1925) | 0.92 in (1971) |
| August 4 | 108.0°F (1922) | 61.0°F (1925) | 2.28 in (1971) |
| August 5 | 107.1°F (2011) | 57.0°F (2010) | 0.62 in (2024) |
| August 6 | 107.1°F (1924) | 62.1°F (1973) | 0.96 in (1937) |
| August 7 | 108.0°F (1922) | 64.0°F (2010) | 3.38 in (1974) |
| August 8 | 107.1°F (1924) | 61.0°F (2010) | 1.80 in (2017) |
| August 9 | 108.0°F (2023) | 59.0°F (2010) | 2.50 in (1983) |
| August 10 | 109.0°F (1947) | 59.0°F (2010) | 0.80 in (1915) |
| August 11 | 109.9°F (1936) | 60.1°F (2010) | 2.02 in (2024) |
| August 12 | 108.0°F (1969) | 60.1°F (2010) | 1.12 in (1966) |
| August 13 | 109.0°F (1925) | 59.0°F (1931) | 2.67 in (1920) |
| August 14 | 107.1°F (1923) | 57.0°F (1967) | 1.62 in (1996) |
| August 15 | 106.0°F (1925) | 60.1°F (1967) | 2.56 in (2016) |
| August 16 | 107.1°F (1925) | 59.0°F (2010) | 2.04 in (1972) |
| August 17 | 108.0°F (1923) | 57.9°F (2010) | 0.84 in (1906) |
| August 18 | 107.1°F (1923) | 57.9°F (2010) | 1.00 in (1915) |
| August 19 | 108.0°F (1924) | 59.0°F (2010) | 2.60 in (1932) |
| August 20 | 107.1°F (1917) | 60.1°F (2010) | 1.02 in (1967) |
| August 21 | 108.0°F (1924) | 57.9°F (1940) | 1.23 in (2016) |
| August 22 | 108.0°F (1917) | 57.0°F (2010) | 4.02 in (1998) |
| August 23 | 111.0°F (1917) | 55.0°F (1949) | 2.00 in (1923) |
| August 24 | 107.1°F (1924) | 55.9°F (1949) | 3.23 in (1996) |
| August 25 | 108.0°F (1924) | 59.0°F (1949) | 1.93 in (1962) |
| August 26 | 107.1°F (1922) | 57.9°F (1949) | 3.75 in (1947) |
| August 27 | 109.0°F (1923) | 55.0°F (2010) | 5.39 in (2017) |
| August 28 | 106.0°F (2011) | 54.0°F (2010) | 2.20 in (1923) |
| August 29 | 106.0°F (1943) | 50.0°F (2010) | 2.10 in (1946) |
| August 30 | 109.0°F (2011) | 57.0°F (2010) | 3.15 in (1946) |
| August 31 | 108.0°F (1923) | 60.1°F (1915) | 4.41 in (1981) |