Severe thunderstorm watch in effect for North Texas and Brazos Valley.

North Texas, including Dallas-Fort Worth, is under a severe thunderstorm warning until 10 p.m. Wednesday, with the possibility of "giant" hail up to 4 inches in diameter and damaging winds up to 70 mph. A tornado warning was issued for parts of Van Zandt County. Counties to the south of Dallas toward Central Texas are under a heat advisory Wednesday. The National Weather Service is monitoring the potential for severe thunderstorm developments Wednesday afternoon and evening across Central Texas.