The sun had barely risen on the West Coast yesterday when the Associated Press reported that “Washington was abuzz with speculation” that Judge Edith Clement of the U.S. Court of Appeals in New Orleans had been tapped to replace Justice O’Connor on the Supreme Court.

The speculation shifted into high gear when, hours later, the White House press secretary, Scott McClellan, said President Bush would announce his nominee during a prime-time televised announcement. The countdown had begun, and there were less than eight hours remaining to figure out who the nominee would be.

On CNN, Jeffrey Toobin called Judge Clement “the leading suggestion” for the vacancy.

Bloomberg News reported that “Republican activists with ties to the White House are anticipating that Bush’s choice will be Judge Edith Brown Clement.”

The AP moved photos of Judge Clement’s house in New Orleans and her husband chuckling outside.

Slate even published a pronunciation guide to Judge Clement’s name, “You Say CLE-ment, I Say cle-MENT,” complete with a recording of one of her law clerks pronouncing it.

By midafternoon, lawmakers and policy analysts were treating the speculation as nearly confirmed fact. Pointoflaw.com, a Web site sponsored by the Manhattan Institute, sent out e-mail with links to sites that featured Judge Clement’s biography and judicial opinions, noting “speculation is running rampant” that she would be the president’s pick.

Senator Schumer, in remarks on the Senate floor, warned that “whomever the nominee, whether Edith Clement as many are rumoring, or another, there will be many tough questions on a broad range of issues.”

By early evening, ABC News was reporting that, according to its sources, the nominee wouldn’t be Judge Clement after all. The AP revised its story, saying “the day began with an intense focus” on Judge Clement, and it moved photos of other women named as likely candidates for the job.

Finally, just more than an hour before Mr. Bush was to make his announcement, CNN reported that Mr. Bush would nominate Judge John Roberts Jr. of the D.C. Circuit Court. At the 11th hour, the speculation was correct.

“Judge Roberts has served his fellow citizens well. And he is prepared for even greater service,” Mr. Bush said.

The day’s news hammered home a recurring lesson for journalists: Just because a tornado of speculation revolves around one theory, it does not make the theory true. It’s a lesson some reporters may have pondered last night before shaking their heads and moving on to the next story: speculation about Judge Roberts’s chances of confirmation.