Feb. 17 Sonic Drive-In 3415 Atlanta Highway, Flowery Branch Score: 87, Grade: B Walk-in cooler ambient temp at 46 degrees and milk temp at 44.7 degrees, chili at 45 degrees and whip cream at 45 degrees. Small prep cooler not keeping foods at 41 degrees or less. Foods temped at 44 degrees that were not in ice containers in cooler.