NASHVILLE, Tenn. — Ilsa Paulson is the first American winner in the 11-year history of the Country Music Marathon, a race she entered after volcanic ash from Iceland kept her from flying to Italy for a marathon.

Paulson crossed the finish line in 2 hours, 33 minutes, 41 seconds Saturday, when a tornado watch for the Nashville area prompted organizers to divert slower runners to the half-marathon course. Storms four hours after the start forced runners to take shelter at LP Field, home of the Tennessee Titans.

Paulson had been scheduled to run in Padua, Italy, on Sunday. The 21-year-old from New York City changed plans after the eruption in Iceland forced flight delays and cancellations throughout Europe.

William Najanjo of Colombia won the men's division in 2:15:39.