I always love when people from San Antonio call the city humid.
They obviously haven't lived in anyplace hot and humid before.
In the afternoons the average humidity in the city is around 45-50% which is considered to be within the ideal range, though may seem sticky in hot seasons. It can be more humid in the mornings, but it is cooler then. I would love to sentence the people who complain about the San Antonio weather to a Summer in Houston and the Winter in Dallas. Then they would realize how nice San Antonio actually is. It does average in the 90s in the summer, so it is warm, though not necessarily warmer than most of New Mexico.
There is more to do in San Antonio in the Summers, as the theme parks in the area are open full time, and there are more overall activities. However, the ideal weather for the area is in the Spring and Fall, when the days are warm and the nights are cool. However, since the kids are in school, the theme parks are closed most of the time during the week. It gets too cool for many of the outdoor activities in the Winter months, so many of the areas close for a couple of months for cleaning and construction during that time. But Christmas along the Riverwalk is nice.
There are many cultural events in the city which are low cost or free.
If you want to go to the theme parks buy the tickets online as the price is much lower than at the gate.