Despite Dvorak satellite estimates of , reconnaissance aircraft indicated Isidore remained a Category 3 hurricane, with pressures dropping to , typical of a Category 4 hurricane. It is the lowest minimum pressure ever observed for an Atlantic hurricane which did not exceed Category 3 intensity. With nearly ideal conditions for development, Isidore was forecast to reach winds of over the northern Gulf of Mexico. High pressures to its north forced it southward, and Isidore made landfall at Telchac Puerto in Yucatán as a major hurricane on September 22. It weakened rapidly as it nearly stalled over Yucatán, and was only a minimal tropical storm after being inland for 30 hours.