Jessie J showcases a slower number, 'Thunder', in front of 16,000 fans. This image appears in the gallery:Amazing Pictures From The 2013 Jingle Bell Ball Sunday Show 84. Jessie J showcases a slower number, 'Thunder', in front of 16,000 fans. Picture: Richard Johnson 91 images See the full gallery: Amazing Pictures From The 2013 Jingle Bell Ball Sunday Show