Vienna ? Former U.S. President Bill Clinton and others ran for cover Saturday as the opening of a flashy Austrian AIDS gala was cut short by a fierce thunderstorm.

Appearances by Clinton, burlesque dancer Dita Von Teese and Patti LaBelle had to be skipped after authorities issued a weather warning and ordered the packed square in front of Vienna’s city hall to be cleared.

The 18th annual party — a fundraiser for people with HIV and AIDS — each year attracts thousands of revelers in quirky costumes who dance until dawn in the vast neo-gothic building — often wearing nothing more than the bare minimum.

Take Hans Peter Aigner, a 44-year-old from Innsbruck, whose outfit consisted of white and blue body paint, black patent leather plateau boots and tiny white hot pants.

“This is my twelfth Life Ball — we’re never going to miss another one,” he said.