Philadelphia has postponed its "Holiday Celebration and Treelighting Spectacular," originally scheduled to start at 5 this afternoon.

Because of heavy rain in the forecast, the festivities have been switched to Thursday, when conditions should be cooler but clear.

This year, the city has a 38-foot-tall artificial tree, with 5,800 small LED lights and 672 silver-and-red ornaments, set in JFK Plaza (LOVE Park), amid the 50 wooden shops of the medieval-style Christmas Village. The five-star star atop the tree has 129 light by itself.

Plans include singers, performers and characters from various shows, and the tree-lighting, with Mayor Nutter and his wife, Lisa, flipping a switch just before 6 p.m.

Singing will be the Municipal Employees Choral Ensemble and the casts of two musicals in town this month and part of next - The Jersey Boys, playing at the Forrest Theatre, and The King & I, at the Walnut Street Threatre.

"Special appearances" will include the Mouse King from Pennsylvania Ballet's The Nutcracker, running all month at the Academy of Music, and characters from a movie based on Dr. Seuss' The Lorax that's set to be released in March.

Because of the LED lights, the tree will use about a quarter of the power of conventional lighting for a tree that size - about as much as a common household refrigerator would use, said spokesman Randy Giancaterino.

Sponsoring the event are Kindy's Factory Outlet of South Philadelphia and Kraft Macaroni and Cheese, which has been symbolized for more than a week by a giant yellow noodle with the words "You know you love it" at the corner of 15th Street and JFK Boulevard.