President Obama this morning will nominate U.S. appeals court Judge Sonia Sotomayor of New York to replace retiring Justice David Souter on the U.S. Supreme Court, White House officials said.

If confirmed, Sotomayor, 54, would be the first Supreme Court justice of Hispanic descent and only the third woman ever to sit on the panel. She grew up in a Bronx housing project, went on to Princeton University and Yale Law School, and has stirred controversy by saying that judges’ legal findings are informed by their own life experiences as well as their legal research.

Obama, too, has said jurists’ life experiences are a key part of their legal makeup. He met Sotomayor in person for the first time Thursday at the White House, administration officials say. After spending the weekend at Camp David, he made his decision to nominate her last night.

The 10:15 a.m. announcement will be made in the East Room of the White House, officials said, before Obama leaves Washington for a two-day trip to California and Las Vegas that will focus mostly on fundraising events. Obama has set a deadline of confirming Sotomayor by the start of the Senate’s five-week recess, slated to begin Aug. 7.

Sotomayor has been considered a likely Supreme Court pick if there was an opening while a Democrat was in the White House, hailed for both her compelling personal story and her extensive judicial experience. Since Souter announced his retirement May 1, analysts had widely predicted that she would be Obama’s choice.

“We already know that she is a brilliant lawyer who is committed to ruling based on the Constitution and the law, not on her own personal political views,” said Doug Kendall, president of the liberal Constitution Accountability Center, in an e-mailed statement this morning.

However, she is strongly opposed by conservative groups, who — like her supporters — began to issue statements about her nomination even before it was announced. Even the Obama administration has differed with one of her more controversial decisions, which invalidated results of a firefighter promotion exam in New Haven, Conn.

“Judge Sotomayor is a liberal judicial activist of the first order who thinks her own personal political agenda is more important that the law as written,” said Wendy E. Long, counsel to the Judicial Confirmation Network, in a statement e-mailed to reporters this morning. “She thinks that judges should dictate policy, and that one’s sex, race, and ethnicity ought to affect the decisions one renders from the bench.”

Sotomayor was part of a three-judge panel that upheld New Haven, Conn.’s, decision to scuttle a promotions test for firefighters after the results showed no African Americans qualified for advancement. The white firefighters who would have been promoted said the decision violated federal law and their constitutional rights.

The case was appealed to the Supreme Court, and a ruling is expected before the end of this term. The case went to the high court after an unusual dissent by conservative fellow judges on the U.S. Court of Appeals for the 2nd Circuit, who said Sotomayor and two others tried to bury important federal law and constitutional questions raised by the firefighters’ suit in their ruling.

The Supreme Court seemed unlikely to let the decision stand when it heard arguments in the case last month. The Obama administration took the position that New Haven officials could throw out the results if they were genuinely concerned that the tests were deficient. But it said the lower courts did not do enough to make sure the city was not using that concern as a pretext for scuttling the test because it did not like the results, and told the justices they should send the case back.

Sotomayor’s Puerto Rican heritage would add ethnic diversity to the court. But her Ivy League, East Coast and appellate court background mirrors that of most of the rest of the justices. Court watchers had speculated that Obama might use the vacancy to appoint a state-level judge, or possibly someone who was not a member of the bench — perhaps a governor or current or former legislator.

In addition to Sotomayor, 54, the short list of those under consideration was widely believed to have included three other women — one also a federal judge and two who are high-level administration officials. They were: U.S. Solicitor General Elena Kagan, 49; U.S. appeals court Judge Diane P. Woods, 58; and Homeland security Secretary Janet Napolitano, 51.