Despite the close passage of the storm to the Florida Keys, damage in the area was light and amounted to $175,000. Of this, $125,000 was attributed to structural damage. Hurricane-force winds in the archipelago only lasted 15 minutes and gale-force winds occurred over a 5-hour span. The brevity of damaging winds limited the effects of the storm. Most damage was constrained to downed trees, signs, and power poles. Two trailers were overturned, however, and an oil barge sank in the Key West Harbor. Two people drowned after their shrimp boat was destroyed. In and around the Fakahatchee Strand Preserve State Park, Royal Palms, and Royal Poincianas were defoliated by the hurricane's winds. Downed trees and power lines in Collier County temporarily left many customers without phone and electrical service. Residents in nearby Lee Cypress stated that the effects from Isbell were worse than Hurricane Donna which struck the region as a Category 4 in September 1960.