Helene roared ashore in Florida as a Category 4 hurricane, trapping residents in floodwaters, peeling siding off buildings, knocking out power to millions.

However, much of Florida, including the Tampa Bay region, continued to be under a storm surge warning early Friday morning. That means officials continued to project potentially life-threatening flooding. The worst of the storm is now headed for Georgia.

Forecasters warned the enormous system could create a “nightmare” storm surge and bring dangerous winds and rain across much of the southeast.