Chantal then rapidly moved to the south of a strong subtropical ridge, exposing the northern or north-eastern side of the center because of wind shear. Despite this, the wind shear was not strong enough to stop Chantal from strengthening. Late on July 8 and early on July 9, Chantal sped into an area with more wind shear, and the cloud pattern of the cyclone because disorganized. However, aircraft data and surface observations indicated that the storm reached a peak intensity of and a pressure of as it passed just south of Martinique. Chantal then moved into the Caribbean with a forward speed of around as the system became less organized. On July 10, an Air Force Reserve hurricane hunter aircraft flew into the system, and could not locate a circulation center, which may of been because the circulation was small and moving faster than expected.
