Nation Most powerful hurricane in US history was a nameless storm that rocked Florida on Labor Day 1935 August 29, 2019 John McCarthy, Florida Today Comments Off on Most powerful hurricane in US history was a nameless storm that rocked Florida on Labor Day 1935 On Labor Day that year, some 500 people died as the most powerful hurricane ever to make landfall in the U.S. ripped the Upper Florida Keys to shreds.