Ernst finished her freshman season at Hancock by setting personal-best times in multiple events during the 2018 Western State Conference Championships. She finished 23rd overall in the 100-yard freestyle with a time of 1:07.53, as well as shaved eight seconds off her time to finish 20th in the 200-yard freestyle with a time of 2:30.37. Ernst also cut two seconds off her 50-yard freestyle time. She played basketball and swam at Righetti High School. She plans to transfer to Cal Poly, San Luis Obispo and become a special education teacher. Her favorite sports memory is watching USC win the Rose Bowl.