Temperatures don't drop below freezing too often in Dallas, Texas compared to how many days are over 100 degrees. But when they do, I'm still surprised at how many people operate their sprinkler systems in freezing temperatures.
While there might not be a risk to the sprinklers, you could be damaging your landscaping (not inexpensive to replace). More importantly, you could be creating a road hazard if water accumulates on the road.
Per Billy Jack Sprinkler Company, if you have a relatively new home with sprinklers or are planning to install a sprinkler system, "all cities in the state of Texas now require a rain/freeze sensor that will stop your sprinkler from running on rainy or freezing days".
The device stops the sprinkler from coming on when there is 1/8" of rain or the temperature drops below 34 degrees. As the sensor dries out or the temperature rises, the controller will automatically go back into normal operation.
It's also a great water conservation device. Many cities -- Plano, for example -- offer rebates for installation of these devices if you don't have one already.
If you do have one installed, it's a good idea to test it at least once a year to make sure it's operating as intended.
As always, any time you need help with home repairs or home decor, give me a call. I'm happy to put you in touch with some of the greatest contractors in the area.