Hurricane Sandy will hit southwestern and coastal Maine the hardest but the state will be spared the worst of the storm’s impact.

Dan St. Jean, a meteorologist at the National Weather Service in Gray,  said as of 11 a.m. Saturday it appeared the first clouds from the hurricane will roll into the state on Sunday, followed by heavy rain and gusty wind and a possible storm surge on the coast Monday afternoon and evening.

“We are expecting waves of up to 25 feet that will result in some heavy surf,” said St. Jean.

The worst of the storm, which is expected to make landfall somewhere between Delaware and New Jersey, will be felt in New Jersey, Long Island and the southern Massachusetts coast.

But Maine still will see significant rain, up to 3 inches between Monday afternoon and evening, which could trigger flash flooding in rivers and streams in southwestern Maine.

Winds with gusts of up to 70 mph could whip up a 2-foot storm surge during the high tides at noon and midnight Monday. Flooding is expected in the usual spots, such as Commercial Street in Portland and Camp Ellis in Saco.

“Right now it is very difficult to tell where the storm surge will be,” said St. Jean.

A Category 1 hurricane, Sandy caused 40 deaths as it raged through the Caribbean.

When Sandy hits a large cold front now moving into the East it is expected to evolve into a huge hybrid storm that will linger for days in northern New England.

Unsettled showery weather could continue into Friday, with daytime high temperatures in the upper 50s and lows in the lower 50s.

St. Jean said the National Weather Service does not expect the path of the hurricane to change significantly at this point.

“The wind will be the problem,” said St. Jean.

State emergency officials have warned Mainers to prepare for dangerous weather and stay informed about hurricane forecasts.