One Direction Fans Storm TODAY Show Plaza

One Direction has drawn an estimated 18,000 Directioners to Rockefeller Center, NYPD estimated, all packing into about two New York City blocks outside a temporarily renamed Studio 1D.

"It seems to me this is the biggest crowd we've ever had," Al Roker said.

The fans are eagerly awaiting the group's performance as part of the Today show's Toyota Concert series.

The morning show is trending worldwide on Twitter, and has been since 7:05 a.m. ET, hours before the start of the concert.

Upcoming performances in the Toyota Concert Series include:

AUGUST

30 CHRIS BROWN, #ChrisBrownTODAY

SEPTEMBER
2 FLORIDA GEORGIA LINE & NELLY, #FGLNellyTODAY

23 CHER, #CherTODAY

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