Possible showers and traffic delays aside, the 53rd annual Light Up Night events start at noon, with the tree lighting at the City-County Building. The PPG Plaza tree will be lit at 6 p.m., and 45 minutes later, Macy's festive windows will be unveiled.
The BNY Mellon Fireworks Finale will go off at 9:38 p.m., as Zambelli Internationale fireworks will launch from the Warhol Bridge, synchronized to a live broadcast on 3WS (94.5 FM).
Expect street and sidewalk closures and transit detours throughout Downtown Pittsburgh today.
9 a.m.-midnight: Andy Warhol Bridge, Forbes Avenue at Wood Street and all of Market Square, Graeme, McMaster and Market Streets.
10 a.m.-1 a.m.: Roberto Clemente Bridge.
2 p.m.-11 p.m.: Delray Street between Forbes and Liberty avenues.
4 p.m.-10 p.m.: Fourth Avenue from Wood to Stanwix streets, Commonwealth Place from Liberty Avenue to Fort Duquesne Boulevard.
4 p.m.-10:30 p.m.: Forbes Avenue from Market Square to Smithfield Street.
4:30 p.m.-6 p.m.: Smithfield Street from Fifth to Forbes avenues.
4:30 p.m.-midnight: Smithfield Street from Fifth to Sixth avenues.
6 p.m.-9 p.m.: Liberty Avenue from Fifth Avenue to Stanwix Street, Smithfield from Fifth to Forbes.
6 p.m.-10 p.m.: Inbound Fort Duquesne Boulevard from Stanwix to Clemente Bridge, outbound from Rachel Carson Bridge to Stanwix.
9:15 p.m.-10 p.m.: Rachel Carson Bridge.
9 a.m.-midnight: Both sidewalks on Warhol Bridge.
5 p.m.-10 p.m.: East sidewalk on Clemente Bridge.
6 p.m.-10 p.m.: Riverfront walkway from Sixth to Ninth streets.
8 p.m.-10 p.m.: North Shore riverwalk from PNC Park to Alcoa Building.
Streets around Market Square will close from 9 a.m. to 8 p.m. Saturday for the holiday market grand opening and horse-drawn carriage parade.
Fifty-five Port Authority routes and several suburban commuter buses will be detoured because of street closures. Details at www.portauthority.org.
The authority is adding two-car trains on the Light Rail Transit system and longer articulated buses to accommodate an expected surge in ridership.
More than 40 bus routes will be detoured in Downtown between 4:30 and 7 p.m. Saturday during the carriage parade.