NEW YORK (CNN) -- The weather-delayed delivery of the final two sections of a 408-foot spire to the top of One World Trade Center will take place Thursday morning, weather permitting.
Once the two sections are installed they will make One World Trade Center the tallest building in the Western Hemisphere.
But that installation will not happen until a later date, officials said.
Thursday is the second anniversary of the death of Osama bin Laden, the mastermind behind the September 11, 2001, attacks that toppled the original World Trade Center towers.
But the timing of the delivery is coincidental.
The crowning pieces were scheduled to be delivered Monday morning but had to be rescheduled because of bad weather, according to the Port Authority of New York and New Jersey.
The two pieces form a stainless steel beacon weighing almost six tons and will be the final piece put in place to give the building an iconic height of 1,776 feet, according to a news release from the Port Authority of New York and New Jersey.
Once the architectural structure is complete, it will comprised 18 separate sections of steel and three communication rings. The first -- and heaviest -- steel section was installed in January, weighing more than 67 tons, the news release said.
Port Authority Assistant Director of Media Anthony Hayes said the original design included a radome -- short for radar dome -- but that was rejected because of anticipated servicing and maintenance difficulties. The radome would not have impacted the height, but would have provided an additional design element, which ultimately proved impractical, Hayes told CNN.
The spire will serve a television broadcast facility housed in One World Trade Center, the press release said.
While under construction, One World Trade Center became New York City's tallest building a year ago, standing 1,271 feet above street-level. The building then was 21 feet higher than the Empire State Building's observation deck.
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