The Chicago-area forecast looks to be "picture perfect" for the start of Lollapalooza festival Thursday, but conditions will turn rainy starting Friday afternoon. Street closures around traffic impacts in and around Grant Park, Michigan Avenue and DuSable Lake Shore Drive were already in effect. FridayWhile Thursday will be dry and sunny, showers Friday were expected to develop starting about 2 p.m. to the west. "Still seeing heavy pockets before rain showers shift out of here," starting about 3 p.m.By Saturday evening, conditions were expected to be dry. "We may be looking at wet fields over there in Grant Park," Roman said.