The ceremony itself begins at 8 p.m. Anyone attending the event is encouraged to use mass transit.
Because heavy traffic is expected, NYPD officials are advising drivers to avoid the area around Rockefeller Center and Radio City Music Hall from 3 p.m. to midnight.
All spectators attending the event will have to pass through a security screening prior to entering the tree-lighting area.
Screening areas are being set up at 48th, 49th and 50th streets at both 5th Avenue and Avenue of the Americas. Umbrellas, large coolers, alcoholic beverages, backpacks and/or large bags are all prohibited.
The following streets will be closed from 3 p.m. Wednesday until the event ends:
*48th to 51st Street between Avenue of the Americas and Madison Avenue
*47th Street between 5th Avenue and Madison Avenue
*52nd Street between 5th Avenue and Madison Avenue
After the tree is lit - from Thursday, November 29th until Monday, January 7, 2019 - the following streets will be closed to vehicle traffic on weekdays from 5 p.m. until midnight, and on weekends from 1 p.m. until midnight:
*49th Street between 5th Avenue and Avenue of the Americas
*50th Street between 5th Avenue and Avenue of the Americas
These closures are subject to change, depending on crowd activity, police said.
WATCH the NYPD security briefing
This year's tree is a massive 75-year-old Norway spruce donated by a couple in Wallkill, 60 miles north of New York City.
The tree will burst alive with 5 miles of LED multicolored lights and a 900-pound Swarovski crystal star during Wednesday night's lighting.
It will remain on display until Jan. 7. Then it will be given to Habitat for Humanity to help build homes.
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