A tropical storm system brought heavy rain into San Diego’s South Bay early Tuesday. The most active area before 6 a.m. was south of Interstate 8 where pop-up storms dumped a lot of rain in a short period. The South Bay was getting pummeled, according to NBC 7’s Whitney Southwick. “It’s all coming from what was Hurricane Paine, now Tropical Storm Paine,” Southwick said. “As it continues north, it will continue to weaken.”