How to follow it: The New York Times’s White House and congressional teams will be following all of the developments of the day around Washington and providing real-time analysis during the speech. Visit nytimes.com for coverage throughout the day and a live stream of the address in the evening.

[Read more about the guests at Trump’s 2020 State of the Union.]

On trial by day, on the dais by night, Trump will use his speech to move beyond impeachment.

While tempted to show up at his Senate trial to defend himself, Mr. Trump deferred to lawyers and advisers who warned against it. But in effect, the defendant will now appear in the Capitol in a different format to offer the best case for his presidency, all without having to worry about cross-examination.

Many inside and outside the chamber will be watching to see how or if he directly addresses the constitutional showdown that has been playing out for months. Mr. Trump had hoped to have the trial behind him by now so he could use the nationally televised appearance as a show of victory, but senators delayed a final vote until Wednesday to give speeches explaining their decisions.

As a result, during the day on Tuesday, senators will rise one after another on their side of the Capitol to announce whether they support conviction or acquittal on charges of abuse of power and obstruction of Congress stemming from Mr. Trump’s efforts to pressure Ukraine to help him tarnish Democratic rivals. Then, after dark, the same president they are judging will make his way down the House aisle, shaking hands with lawmakers and laying out his agenda for the year.

If Mr. Trump does address the trial in his speech, it may be less bombastic than his usual fare. While he has been outspoken denouncing what he calls a “hoax” and “witch hunt” against him, the president traditionally has been more measured and less confrontational during his State of the Union addresses, carefully following the texts prepared for him.