Weather forecasters are expecting heavy rain and storm surges Sunday in southern Maine as Hurricane Henri passes by to the south, saving its greatest impact for New York and southern New England.

Henri was upgraded to a Category 1 hurricane in the National Weather Service’s last advisory, and is expected to come ashore as either a weak hurricane or a strong tropical storm, said Donny Dumont of the weather service’s station in Gray. After landing between Rhode Island and Long Island, it’ll take a sharp turn to the east and rapidly lose strength as it passes Maine on Sunday afternoon.

“By the time the storm circulation comes over Maine, it’s going to be a pretty weak blow,” Dumont said on Saturday.

Rain bands headed in off the ocean Sunday afternoon could bring torrential downpours and storm surges, which have meteorologists concerned about rip tides along Maine beaches. Those conditions may last between 12 and 18 hours, and likely will include localized flash flooding.

Needless to say, Mainers and summer visitors should reconsider any plans for swimming.

At the height of the storm, winds could reach 25 to 30 mph along the ocean, Dumont said. The remnant of the tropical depression is expected to pass over Maine on Monday night and continue into early Tuesday.

New England hasn’t taken a direct hit from a hurricane since Hurricane Bob in 1991. That storm, a stronger Category 2 hurricane, killed 17 people and created $1.5 billion in damage. More recently, New York City suffered extensive damage, including 44 deaths and over $1 billion in damage, from Superstorm Sandy in 2012.

This time, officials in New York, Connecticut, Massachusetts and Rhode Island are expecting extensive power outages, flooding and potentially dangerous storm surges in coastal communities.

The National Weather Service’s outlook was considerably less sanguine for southern New England. In Litchfield County, an inland part of Connecticut, the agency warned, “major flooding may prompt many evacuations and rescues.”

“Floodwaters may enter many structures within multiple communities, with some structures becoming uninhabitable or washed away,” the weather service said in an advisory for Litchfield County on Saturday. “In many places, floodwaters may cover escape routes.”

Beyond that, residents should expect “life-threatening wind” that may cause structural damage to homes, turn ordinary objects into dangerous projectiles and knock out power and communications lines.

Up north, the Maine Emergency Management Agency on Friday encouraged residents to prepare for severe storm conditions, including by charting local evacuation routes, securing loose belongings outside, removing boats from the water and building an emergency kit.

Recommended items for emergency kits, as well as MEMA’s full list of steps to prepare for the storm, are available here.

In Kittery, town officials closed Fort Foster, Pepperell Cove Pier and the Traip boat ramp in anticipation of high winds on Sunday and Monday. They also warned residents to avoid roads that are frequently impacted by storm surges and flooding.