In southern Aroostook, the Meduxnekeag River in Houlton was rising. The water was creeping up over the banks Saturday, April 20, 2019, and onto the fitness paths in Riverfront Park. Credit: Jen Lynds

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. “There is going to be some flooding in some areas, but the larger rivers have a longer lag time. The problems with those will begin to show over the next day or two.”

Mignone said meteorologists are monitoring the rainfall and water levels of larger rivers in northern, north-central and eastern Maine. Warnings have already been issued for flooding along the Kennebec River in Augusta and in Skowhegan, NWS Gray meteorologist Derek Schroeter said.

“We’re expecting the rivers to rise throughout this afternoon and potentially stay at that stage into tomorrow,” Schroeter said.

While most of the heavy rain has already fallen, heavy to moderate rain will continue in southern, central and western Maine over the course of the afternoon on Saturday. In other parts of the state, rain and showers will be more localized.

On top of the rainfall, warmer temperatures and fog are helping to melt what is left of the snowpack across the state, which leads to rising water levels in rivers and streams, Mignone said. Further compounding water level rise is the risk of ice jams forming with ice still left in some of the state’s rivers, he said.

Along the coast, high astronomical tides may cause beach erosion and wave splash over, Schroeter said, especially at high tide around 1 a.m. on Sunday.