San Antonio Seasonal temperature break down - The average median temperature March through May is approximately 70°F with highs averaging at 81°F and lows averaging at 61°F. June through August has an approximate average median temperature of 85°F with highs averaging at 98°F, lows typically average at 75°F. Average median temperatures September through November average out at 71°F, high temperatures average out at 86°F and lows average at 59°F.
The average median temperature December through February is approximately 55°F with highs averaging at 68°F, lows average out at 45°F.
The average San Antonio annual median temperature averages out at approximately 70°F. The coldest month in San Antonio is January with a median temperature of 53°F, the average high for the month of January is 65°F with an average low of 44°F. The hottest month in San Antonio is August with an approximate median temperature of 88°F, the average high for the month of August is 102°F with an average low of 78°F.