Taylor Swift has announced she will give her fans a chance to see her Speak Now tour before it officially kicks off later this month. The singer will open the last dress rehearsal on May 21 as a fundraiser with all proceeds going to the victims of last week's devastating tornadoes in the Southeast.

For the special event, titled Speak Now ... Help Now!, approximately 13,000 people will get the chance to see Taylor's full show at Nashville's Bridgestone Arena, one week before the North American leg of the superstar's Speak Now world trek kicks off May 27 in Omaha, Neb.

"I was watching the coverage of the tornadoes backstage at rehearsals, and I wanted to do something for the families affected by the damage," says Taylor. "I've never opened a rehearsal to the public before, but I felt that inviting my fans to the last rehearsal for the Speak Now tour would be a great way to raise money."

Numerous tornadoes raged through seven states in the south, including the hardest hit, Alabama, killing 329 people and literally destroying numerous businesses, schools and homes.

Taylor generously donated to relief efforts in Japan, New Zealand and Australia earlier this year, while she donated to various Nashville flood relief efforts last year. She also performed during 2010's Nashville Rising benefit concert, organized by Tim McGraw and Faith Hill.

The reigning ACM Entertainer of the Year, who has been in rehearsals with her band for the last few weeks, forewarns the fans that there might be some changes during the show, as it is still a rehearsal. "We'll probably still be doing some fine-tuning to the show that night, since this will be a true rehearsal," she notes, "but I feel like it is so important for me and my fans to help if we can."

Ticketing information and Speak Now ... Help Now! details will be available and updated beginning Monday (May 9) at Taylor's official website. One-hundred percent of all ticket sales will go directly to help tornado victims.

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