Gal shot a 5-under-par 67 at the Magnolia Grove Crossings Course on the Robert Trent Jones Golf Trail for a two-day total of 137.
Amy Yang was a shot back and alone in second place after posting a 68. Tied for third at 139 were Karen Stupples, Song-Hee Kim and Stacy Lewis, who recently grabbed the tour's first major title of the season at the Kraft Nabisco Championship.
LPGA Tour Hall-of-Fame member Se Ri Pak was among those tied for sixth at 140.
Gal bogeyed both the ninth and 10th holes and stood at even par for the day when she stepped to the 11th tee. She then played the final eight holes in 5-under. Her round was highlighted by a chip-in from 30 feet for a birdie at the par-4 12th.