Average Weather/What to Pack
Located in the heart of Texas, San Antonio is no stranger to hot summers. For the most part, the Alamo City experiences a steady climate -- mild in the winters and steamy all summer. As for most parts of mid and Southern Texas, snow is rare. In fact, average temperatures in the winter hover around 60.
Transportation
Cars are important in San Antonio. If you plan to stick around the downtown/Riverwalk area, you can make it using your feet. However, if you're going to explore other areas of the city, including the Hill Country and Fiesta Texas, you'll definitely need a car.
The local transit system, the VIA Metropolitan Transit Service, provides service throughout the city and links all major tourist spots, including the Alamo and Riverwalk. Passes can be purchased in advance to historic and cultural attractions. If you're downtown and you want to get to Six Flags and Sea World, the VIA operates express routes to these destinations.
Don't depend on taxi cabs. The city is quite spread out and unless you're just staying within a certain section, cab fare becomes expensive.
In-Season Costs
San Antonio is pretty reasonable as far as prices go. There is no time of the year that prices significantly increase, although you might expect to pay a little more during Fiesta (April), the city's largest festival/party. Make sure to reserve your room in advance.
Day Trips
Austin, the state capital, is only 77 miles from San Antonio. It's definitely worth the trip. The "Live Music Capital of the World" is home to the tallest state capitol building in the U.S., in addition to the Lyndon Baines Johnson Presidential Library and the University of Texas.
San Marcos. San Marcos is located about 30 minutes outside of San Antonio. This town is great for outlet shopping.