With around eight inches of rain anticipated to fall before next week, forecasters are cautioning Grass Valley and surrounding area residents on the possibility of flooding. “For small streams, keep a watch on it and be prepared,” said Holly Osborne, a meteorologist with the National Weather Service in Sacramento. A series of rain storms is expected to dump rain on western Nevada County, starting Wednesday and possibly lasting into next week, Osborne said. The weather system is coming from Alaska but is tapping into moisture from the Pacific Ocean, keeping temperatures above freezing. High temperatures throughout the week are expected …