In February 1999, Weiss won his first senior national title at the U.S. Championships in Salt Lake City, Utah. The following month, he was awarded the bronze medal at the 1999 World Championships in Helsinki, Finland. After recovering from a stress fracture in his left ankle, Weiss defended his national title at the 2000 U.S. Championships in Cleveland, Ohio and won bronze at the 2000 World Championships in Nice, France.