1947 Project Cirrus Hurricane - Meteorological History

Meteorological History

In early October 1947, the origins of Hurricane Nine were detected north of Panama in the Intertropical Convergence Zone. On October 9 at 0600 UTC, a minimal tropical storm was estimated to have formed with maximum sustained winds near 40 miles per hour (64 km/h); thereafter it moved north by west. By October 10, the storm accelerated and began strengthening steadily, reaching a peak intensity of 65 mph (105 km/h) before striking land just before 0600 UTC on October 11 south of Pinar del Río in Pinar del Río Province, Cuba. The center of the storm then began turning to the northeast before passing near Batista Field, which recorded wind gusts of up to 57 mph (92 km/h). Six hours after leaving northern Cuba, the storm rapidly became a hurricane, equivalent to Category 1 on the Saffir-Simpson Hurricane Scale. Just after 00 UTC on October 12, the hurricane struck Florida just north of Cape Sable, and just before 1200 UTC it left the Miami metropolitan area near Pompano Beach—the same area that had been hit by the 1947 Fort Lauderdale hurricane one month previous—with winds of 85 mph (137 km/h). Unusually, the hurricane strengthened over land as it passed over South Florida, a phenomenon also observed in Tropical Storm Fay (2008), which struck the same region.

After leaving South Florida, the hurricane passed north of the Bahamas while maintaining its intensity, although a lack of weather observations near its eye prevented forecasters from appraising its exact location and movement. Early on October 13, the hurricane slowed substantially and began turning to the north; by afternoon, the cyclone had shifted course and turned westward, toward the Southeastern United States. Early on October 14, a reconnaissance aircraft penetrated the storm but only reported winds of up to 55 mph (89 km/h). As the storm continued moving west, another mission that entered the center around 00 UTC on October 15 reported hurricane-force winds. At 12 UTC that day, the storm struck 15 miles (24 km) south of Savannah, Georgia, with winds of 85 mph (137 km/h). At the time, the coverage of hurricane-force winds was small, extending about 20 miles (32 km) in all directions from the eye. The storm weakened slowly as it crossed inland areas of Georgia, but by 00 UTC on October 16 it weakened to a tropical storm, dissipating 18 hours later over Alabama.