[UPDATE BELOW] President Donald Trump's return to New York City will be relatively brief—he's expected to arrive at JFK Airport around 3 p.m., according to a schedule from the White House press office, and will reportedly spend the night at his New Jersey residence. But the gridlock in Manhattan is expected to be intense while he's here.

Trump is in town for a ceremony at the Intrepid to make the 75th anniversary of the Battle of the Coral Sea, in which Australia and the United States combined forces against Japan for a hard-fought strategic Allied victory during World War II. Trump is reportedly meeting Australian Prime Minister at the Peninsula Hotel, at Fifth Avenue and 55th Street, before heading to the Intrepid.

Gridlock Sam breaks down the traffic issues:

POTUS will arrive mid-afternoon today, Thursday, at the Wall Street Heliport, and go straight to midtown, shutting down the FDR all the way to 63rd Street. His motorcade will exit the FDR, and go to Fifth Ave. via the mid-50s; traffic will be frozen as it passes through.

The president will remain in Midtown until mid-evening, at or within a few blocks of Trump Tower. From mid-afternoon to early evening, please avoid Fifth and Madison Avenues. and cross streets in the 50s; turbulence will abound along avenues east to west, but near Trump Tower, all streets will be impassable.

Mid-evening, POTUS will leave Trump Tower, his motorcade heading back down the FDR, passing through the Battery Park Underpass, and up the West Side Highway to the Intrepid at 46th Street. This will close the West Side all the way from the Battery to Midtown for the evening. Then, after the Intrepid, it’s back to the Wall Street Heliport via the West Side and the Underpass, for departure.

Trump-lock will be widespread throughout the day. When the motorcade is on the FDR, expect major delays entering the Brooklyn Bridge (which could impact the Manhattan Bridge), the Brooklyn-Battery Tunnel, and the Queensboro Bridge, (which will cause diversions to the Queens-Midtown Tunnel).

When the motorcade makes its way along West St/West Side Highway, expect significant backups at Tenth and Eleventh Aves. and beyond, and at the Lincoln and Holland tunnels, as well as major crosstown streets.

Clearly, if you're driving in Manhattan today, you're in for a real treat. Street closures will also impede pedestrian and cyclist travel in places, and NYC Ferry service at Wall Street / Pier 11 may be impacted between 3 and 5 p.m., due to Marine One's arrival at the helipad there.

Multiple demonstrations are planned, with a large one anticipated at the DeWitt Clinton Park on the west side, starting at 2 p.m. The group Rise and Resist will also hold a rally at West 44th Street and 12th Avenue at 3 pm, while the New York Immigration Coalition and Immigrant Action Fund has organized a protest at Trump Tower at 6 pm.

Trump is scheduled to give a speech at the Intrepid at 7:20 p.m., and will then spend the night and weekend in Bedminster, NJ, at the Trump National Golf Course ("Camp David North").

Update 1:32 p.m.: Trump's schedule has just been updated—the President will be arriving a couple of hours later than expected, with a 6:15 p.m. landing at JFK now scheduled. He'll then proceed directly to the Intrepid, where he'll meet with Prime Minister Turnbull at 7:15, followed by a speech at 7:45 p.m.