Pope Francis to Celebrate Outdoor Mass at Catholic U. | NBC 10 Philadelphia
Pope Francis in Philly

Pope Francis in Philly

Look Back at the Pontiff's Historic Visit

Pope Francis to Celebrate Outdoor Mass at Catholic U.



    Pope Francis delivers his blessing during his weekly general audience, in St. Peter's Square, at the Vatican, Wednesday, April 15, 2015. (AP Photo/Andrew Medichini)

    Estimates for attendees at a mass led by Pope Francis in Philadelphia this September remain at 1.5 million as another mass in Washington D.C. was added to the pontiff's schedule.

    "At this point, we don't anticipate the numbers [in Philly] to be any lower," said Meg Kane, a spokeswoman for the World Meeting of Families event set to take place in Philadelphia from Sept. 22 through Sept. 25.

    The Archdiocese of Washington said the pope will celebrate mass on Sept. 23 outside of the Basilica of the National Shrine of the Immaculate Conception.

    The archdiocese says details are still pending. The congregation is expected to assemble around the basilica on the university mall.

    Andrew Medichini/AP

    Kane did not confirm the Catholic University mass and said Pope Francis'  official schedule will come from the Vatican.

    Along with the service in Washington D.C., the pope is expected to meet with President Barack Obama on Sept. 23, according to the White House. And House Speaker John Boehner has said the pope will address a joint session of Congress on Sept. 24. A stop in Cuba ahead of his arrival in the U.S. was confirmed by the Vatican last week.

    When asked if the jam-packed schedule could overrun Pope Francis, 78, before he arrives in Philly, Kane declined to comment except to say the "question is better suited for the Vatican."

    Despite the sparse details, Kane said one thing was certain for his Philly trip. "He will have a wonderful visit here," she said.

    Previously, Pope Benedict XVI visited Catholic University in 2008 and also celebrated Mass at Nationals Park.