Update: The city’s current irrigation guidelines limit watering to once a week, between the hours of 6:00 pm and 10:00 am, using a sprinkler or sprinkler system. Hand watering can still be done at anytime.
On the heavy clay soil that most of us “enjoy” in the Coastal Bend, a long and slow watering once a week will give your lawn all the water it needs. It is good for it to dry and stress just slightly before the next watering, and once a week is about right for that. Watering deeply but infrequently trains roots to grow deeper, giving better drought resistance, and allowing the top few inches of soil to dry slightly between waterings discourages fungus problems.
Here is a website for the best method for maximizing watering efficiency: Cycle & Soak Method of Lawn Irrigation.
If you live on the few sandy areas in the Coastal Bend your watering will be different. Water multiple times per week with a shorter duration, or eliminate turf and use only highly drought tolerant plants.