Saffir–Simpson hurricane wind scale
Beyond August 13, Yancy continued to follow a westward track, but it did so rapidly. This period of rapid movement lasted for two days, with Yancy moving into an area under the influence of an intensifying subtropical ridge to the north. At 1200 UTC on August 16, the JTWC determined that Yancy had strengthened into a Category 1-equivalent typhoon on the Saffir–Simpson hurricane wind scale (SSHWS).