Once you know the purpose of your trip, you can pick a season. Not surprisingly, temperatures are most comfortable during spring and fall. Winter is generally very mild. Freezes seldom occur. Snow is practically unheard of.
Summer can be quite unpleasant.
Daytime highs can reach into the 90s during July and August, but the humidity makes it seem hotter than it really is. Beaches can get crowded during the month of March when thousands of spring breakers flock to the area. However, it is possible to get away from the crowds. Major holidays also bring large crowds to area beaches. The lines at the Port Aransas ferry can become quite long.