As rain continues to fall Saturday, the combination of warmer temperatures and melting snow has prompted meteorologists to issue flood warnings for parts of the state this weekend. All of southern, western and most of coastal Maine, with the exception of York County, is under a flood watch until further notice, according to a meteorologist at the National Weather Service station in Gray. Most of central and northern Maine, including Penobscot and Piscataquis counties, is also under a flood watch, according to the National Weather Service station in Caribou. “The biggest, immediate issue is the smaller streams which respond quicker than the larger rivers,” NWS Caribou meteorologist Tony Mignone said.