O'Connor will lead the 117th annual Rose Parade on Jan. 2 and toss the coin to start the college championship Rose Bowl Jan. 4.
The 2006 parade with the theme, "It's Magical," is taking place on Jan. 2 because it is never held on Sunday, organizers said in a news release.
Tournament of Roses President Libby Evans Wright made the announcement in a Washington rose garden.
O'Connor said she had fond memories of watching the annual New Year's parade as a child.
"The experience was indeed magical and I have kept it with me," she said. "I'm looking forward to sharing this parade with my grandchildren."
O'Connor says she is stepping down from the court as soon as a successor is confirmed.
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