The National Weather Service issued a tornado watch for much of North Texas Thursday afternoon, hours after a line of storms dumped rain across parts of the area. The watch, which covers Dallas, Tarrant, Collin, Denton, Parker and about 40 other counties, is in effect until midnight Thursday. Meteorologist Greg Patrick said isolated storms are expected to develop this afternoon along a line stretching from Abilene north to just east of Wichita Falls, and should move east around 40 mph. They could produce heavy winds and hail, and some tornadoes could develop as a result, primarily to the north of...