Officials said they will conduct a test of the Outdoor Warning Siren system for Cedar Hill, DeSoto and Duncanville Thursday afternoon.
The Southwest Regional Communications Center will begin the test at 2 p.m. unless there is inclement weather or overcast skies.
SRCC officials said they want to ensure they can activate all three cities' sirens simultaneously and that they are operational for severe weather season.
Officials did not say whether Thursday's test is related to the 156 Dallas sirens that were hacked last weekend.
