Florida residents prepared for a heavy blow from Hurricane Helene as the Category 4 storm churned northward Thursday, prompting warnings of pounding rain and a storm surge that could create “unsurvivable conditions” in some areas.

Hurricane Helene made landfall in Florida’s Big Bend as a Category 4 storm late Thursday, knocking out power in over a million homes and businesses and causing at least one death in the state as the National Hurricane Center warned of life threatening winds and catastrophic storm surges.

It’s already battering the state’s west coast with tropical storm-force winds and has caused hundreds of thousands of power outages.