The track of Hurricane Henri appears to be shifting slightly more east on Saturday night.

Landfall now appears possible on far eastern Long Island or southern New England, anywhere from eastern Connecticut to Rhode Island to southeastern Massachusetts on Sunday afternoon. Earlier in the day, it appeared as though the storm might hit central Long Island.

The storm was moving quickly -- 21 mph -- and still maintaining hurricane strength.

Henri is expected to either be a weak hurricane or strong tropical storm on Sunday morning or early afternoon as it moves over or just east of Long Island and eventually into southern New England through the day on Sunday.

Rail service in parts of New York and Connecticut will be halted Sunday due to Henri.

The Long Island Rail Road will be suspending service east of Patchogue on the Montauk Branch and on the Greenport line.

Metro-North, which serves New York and Connecticut, will be suspending service on the Wassaic Branch of the Harlem Line and on the entire New Haven Line, including the New Canaan, Danbury and Waterbury branches.

In Connecticut, service on the rail lines Shore Line East and Hartford Line is suspended starting Sunday "until further notice."

Amtrak also announced it would be canceling all Northeast Corridor service, including Northeast Regional and Acela, between New York and Boston on Sunday.

Flight cancellations are also expected in the region.

"Port Authority expects flights to be canceled," Gov. Andrew Cuomo said during a briefing Saturday. "Obviously I would check with your airline before you go to the airport tomorrow into Monday, maybe Tuesday."

New York City Mayor Bill de Blasio defended continuing on with its "We Love NYC Homecoming Concert" Saturday evening, as the city prepares for Hurricane Henri.

"Since the real impact is not expected until well after the concert, we believe absolutely we can do both these things at once," de Blasio said during a press briefing Saturday, as the concert was set to kick off in Central Park with performers including Bruce Springsteen and Patti Smith.

The mayor urged concertgoers to go straight home at the end of the night. "If you're going to the concert ... go home right after and get ready for tomorrow," he said.

De Blasio, who declared a state of emergency for NYC earlier on Saturday, said the city is preparing for heavy rain, wind and downed trees.

-ABC News' Matt Foster

President Joe Biden held a call with the governors of six northeastern states Saturday to discuss Hurricane Henri, the White House said.

The governors are working with Federal Emergency Management Agency and the National Guard to prepare for possible "widespread power outages, coastal storm surge, and inland flooding," the White House said in a statement.

FEMA has pre-positioned over 700 response personnel, meals, tarps and generators in the region.

"On the call, the President made clear that states have the full support of the Federal government to aid local emergency response efforts," the White House said.

Those on the call included New York Gov. Andrew Cuomo, who is in his final days of office after resigning earlier this month following sexual harassment allegations. His successor, Lt. Gov. Kathy Hochul, also joined the call, along with the governors of Connecticut, Massachusetts, Maine, New Jersey and Rhode Island.

The center of Tropical Storm Henri is currently passing near Block Island, Rhode Island, as it marches toward southern New England.

The system is about 15 miles east of Montauk Point, New York, and about 50 miles south-southwest of Providence, Rhode Island. It is moving north-northwest at 12 mph with 60 mph max sustained winds.

Wind gusts of 69 mph have been reported in Point Judith, Rhode Island, and 65 mph in Block Island, Rhode Island.

The latest track has the storm moving northwest before making landfall near the border of Connecticut and Rhode Island Sunday afternoon.
Tropical storm warnings remain in effect from New York to Massachusetts.

-ABC News’ Samantha Wnek