An area of low pressure in mid-Atlantic generated active thunderstorms for several days and eventually organized into Tropical Depression Nine on 27 September and a tropical storm by 28 September. By that time it was about east-southeast of Bermuda. It became a hurricane on 30 September, and passed about east of Bermuda before swinging northwards towards Newfoundland. As it was still a strong tropical storm near the Avalon Peninsula, tropical storm warnings were issued on 2 October due to the potential for high winds. Isaac passed to the southeast of Cape Race late that afternoon. The Canadian Hurricane Centre reports that if Isaac had tracked just 50 to 100 km (30 to 60 miles) further north than it did, the St. John's area would have experienced much higher winds than the peak gust of it received.